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Departments of Obstetrics and Gynecology, and *Anatomy, Hahnemann Medical College and Hospital, Philadelphia, Pennsylvania 19102, U.S.A.
(Received 9 September 1974)
Since the cellular composition of peritoneal fluid is altered by species, sex (Davis & McGowan, 1968), the oestrous (McGowan & Davis, 1968) and menstrual cycles (McGowan, Davis, Stein, Bebon & Vaskelis, 1968) as well as pregnancy (McGowan, Davis & Kriesler, 1968; McGowan & Davis, 1969), we believe that the cellular content of peritoneal fluid is affected in a characteristic manner by administration of hormones. Testosterone injected into castrated mice increases the percentages of mesothelial cells and histiocytes in serous fluid, with a corresponding decrease in bare nuclei (Davis, McGowan & Villanueva, 1969). On the other hand, oestrogen given to ovariectomized mice reduces the proportion of mesothelial cells and causes 'daisy cells' to appear in aspirated fluid (McGowan & Davis, 1970). Subcutaneous administration of cortisone also decreases the proportions of mesothelial
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Little or no attention has been given to the action of male hormone on the cellular composition of peritoneal fluid. Injections of testosterone into mice increased the number of monocytes, granulocytes and large lymphocytes in the blood (Dunn, 1954). Furthermore, androgens increased haemoglobin, erythrocytes, and the volume of packed cells in normal and castrated male rats (Korenchevsky & Hall, 1945). We have shown that the cellularity of abdominal fluid is influenced by species, sex and the oestrous cycle, and differs during and after pregnancy (McGowan & Davis, 1969 a, b; Davis & McGowan, 1968). The present study attempts to determine the influence of testosterone propionate (TP) on the cytology of the peritoneal fluid of castrated male mice.
We used adult male CF-1 mice and arranged them in groups of 13–16 animals. Four groups of controls consisted of normals, sham-operated mice, uninjected castrates, and castrated mice given daily injections of 0·1
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The possibility that some amino acids may have anti-inflammatory activity was suggested to us by the observation that certain amino acids maintain life and influence liver glycogen deposition in adrenalectomized rats (Davis, 1958; Leathem, 1958). Both biological activities are properties of adrenal steroids which have anti-phlogistic activity. Oral tryptophane increases the survival time of adrenalectomized animals and retards the fall of liver glycogen (Kotake & Inouye, 1955). Epsilonaminocaproic acid has anti-inflammatory activity (Winters & Nuss, 1966). It was, therefore, attempted to inhibit, by injecting l-phenylalanine and l-tryptophane, the infiltration of white blood cells (WBC) and polymorphonuclear leukocytes (PMN) into an area of local inflammation produced by the intradermal injection of 1% gelatin solution into adrenalectomized rats as described by Holtkamp, Bates, Heming, Poetsch, Lawrence & Buell (1956). This method is a reliable procedure for testing the local antiphlogistic activity of glucocorticosteroids.
Adult male Wistar rats (200–-250 g.) were
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ABSTRACT
We report inhibin α- and βA -subunit gene expression in the human corpus luteum and placenta using human α-subunit and bovine βA -subunit nucleic acid probes. In addition, we have demonstrated the presence of immunoreactive and bioactive inhibin in human corpora lutea. Our findings suggest that this tissue is a significant source of inhibin during the luteal phase of the normal human menstrual cycle.
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ABSTRACT
Three cows received injections of thyroxine (T4; 20 mg/day), four cows GH (40 mg/day) and three cows saline (control; 10 ml/day) on days 5–8 of a 16-day experimental period during peak lactation. Milk yield increased 13% in cows given GH (from 14·6 to 16·5 kg/day) and 15% in cows given T4 (from 15·8 to 18·2kg/day) but did not change in control cows. Injection of T4 increased milkfat and lactose content but reduced milk protein content. Injection of GH was without effect on milk composition during the injection period but milk protein rose after injections ceased.
Injection of T4 increased plasma concentrations of T4 and tri-iodothyronine six- to sevenfold, with maxima occurring on day 9. Injection of GH increased the plasma concentration of GH five- to tenfold 5 h after injection. The plasma concentration of insulin-like growth factor I (IGF-I) was increased in cows given GH in both morning (08.30 h) and afternoon (14.30 h) blood samples, the difference being greatest in afternoon samples in which plasma IGF-I content increased from 3·3 to 6·8 nmol/l. Injection of T4 reduced the plasma concentration of IGF-I in morning samples but the concentration in afternoon samples remained relatively constant throughout the 16-day experimental period. The plasma concentration of IGF-II rose in morning samples in all treatment groups to reach a maximum of 200–250 nmol/l by day 9.
The galactopoietic response to injection of GH but not T4 was associated with an increase in plasma concentration of IGF-I. Changes in plasma concentration of IGF-II were not associated with changes in milk yield.
J. Endocr. (1987) 114, 17–24
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ABSTRACT
The metabolic clearance of insulin-like growth factor-I (IGF-I) has been examined in sheep using a radioiodinated hormone preparation (131I-labelled IGF-I). Following i.v. administration, 131I-labelled IGF-I was distributed in a volume equivalent to plasma (60 ml whole blood/kg liveweight) and demonstrated a triphasic pattern of clearance with apparent half-lives (t ½) of 4·0 ± 0·4 (s.e.m.), 52·4 ± 3·4 and 792 ± 26·5 min (n = 10). No significant differences in the t ½ of the three phases were identified in fed compared with starved animals (fed, n = 4, phase 1 = 3·1 ± 0·64, phase 2 = 46 ± 5·9 and phase 3 = 756 ± 27 min; starved, n = 6, phase 1 = 4·6 ± 0·58, phase 2 = 57 ± 3·2 and phase 3 = 816 ± 38·5 min). Similarly, no significant differences in the distribution volume (fed, n = 4, 44 ± 4 ml/kg liveweight; starved, n = 6, 39 ± 2 ml/kg liveweight) or metabolic clearance rate (fed, n = 4, 2·9 ± 0·15 ml/min; starved, n = 6, 3·2 ± 0·5 ml/min) of the IGF-I were found in fed compared with starved animals. Highperformance gel filtration chromatography of sequential plasma samples following injection of 131I-labelled IGF-I revealed three clear peaks of radioactivity which demonstrated markedly different patterns of clearance. These correspond to hormone complexed to binding proteins of 150 000 and 50 000 daltons and to 'free' hormone. While radioactivity eluting in the position of free IGF-I had reduced to negligible levels by 12 min, 131I-labelled IGF-I associated with the intermediate molecular weight binding protein was still detectable 6 h after injection. In contrast, an initial increase in radioactivity associated with the 150 000 dalton binding protein was revealed. This form was cleared from the circulation very slowly, by 8 h it was the only species remaining and it was still detectable 26 h after injection. No significant differences in this pattern of bound and free hormone clearance were found in fed compared with starved animals. While there was apparently no interchange of hormone between the binding proteins in vitro the nature of the decay in vivo indicated the possibility of exchange of IGF-I between the different binding proteins.
J. Endocr. (1987) 115, 233–240
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ABSTRACT
The metabolic clearance of ovine insulin-like growth factor-II (IGF-II) was examined in sheep using 131I-labelled IGF-II. Following i.v. administration the tracer was distributed in a volume similar to that of the vascular space (58-5 ±3.3 ml/kg; mean ± s.e.m., n = 5) and demonstrated a triphasic pattern of clearance. Size-exclusion chromatography of a plasma sample collected 1 min after injection revealed peaks of radioactivity corresponding to hormone complexed to binding proteins of 150 and 40–50 kDa (relative abundance 21 and 65% respectively), a high molecular weight binding protein (>200 kDa; 5%) and 'free' tracer (9%). Chromatography of sequential plasma samples revealed different patterns of clearance for these constituents. Half-lives of 131I-labelled IGF-II complexed to the 150 and 40–50 kDa binding proteins, as calculated from rate constants for their decay, were 351 ± 30 and 9.6 ± min respectively (n = 5). These differ markedly from estimates for the clearance of IGF-I (545 ± 25 min, n = 8, and 34 ± 2.3 min, n = 6) associated with carrier proteins of the same apparent molecular weights. This was reflected in calculated metabolic clearance rates for IGF-I (3.9 ± 0.5 ml/min) and IGF-II (7.8 ±1.0 ml/min). Chromatography also revealed that free IGF-II was reduced to negligible levels by 12 min. In contrast, radioactivity eluting in the position expected for the > 200 kDa binding protein was cleared from the circulation very slowly. However, the small proportion of total radioactivity eluting in these molecular weight regions precluded calculation of decay constants for these species. Tracer degradation was monitored throughout the clearance study and estimated to be <20% at 800 min following i.v. administration. Less than 20% of tracer was cleared into urine over the 24 h of sampling, concurrent with a >90% fall in plasma radioactivity. Tracer in urine was completely degraded.
Journal of Endocrinology (1989) 123, 461–468
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ABSTRACT
Growth hormone stimulates intestinal calcium absorption. This action has been linked to vitamin D metabolism. We have investigated the effects of hypophysectomy and GH treatment on renal metabolism of 25-hydroxycholecalciferol (25-OH-D3). Renal hydroxylation of 25-OH-D3 was measured in vitro using the renal slice technique. Experiments were performed in young F344 rats fed a vitamin D-replete, low calcium diet for 4 weeks. In hypophysectomized rats, renal conversion of 25-OH-D3 to 1,25-dihydroxycholecalciferol (1,25-(OH)2D3) was markedly reduced compared with sham-operated rats. Renal conversion of 25-OH-D3 to 24,25-(OH)2D3 was markedly increased in hypophysectomized rats compared with sham-operated rats. Treatment of hypophysectomized rats with rat GH (rGH) for 10 days resulted in a significant increase in renal conversion of 25-OH-D3 to 1,25-(OH)2D3 and a significant decrease in conversion to 24,25-(OH)2D3. Rat GH treatment caused no significant changes in serum levels of immunoreactive parathyroid hormone. Serum calcium concentrations were similar in all groups, and serum phosphorus was low in hypophysectomized rats. Treatment of hypophysectomized rats with ovine GH for 6 days caused changes which were much less pronounced than those induced by rGH. Renal conversion of 25-OH-D3 to 1,25-(OH)2D3 and 24,25-(OH)2D3 correlated well with growth rate (weight gain). These results suggest that GH, either directly or indirectly, modulates renal metabolism of 25-OH-D3.
J. Endocr. (1984) 101, 333–338
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SUMMARY
The action of pineal extracts on the genital system of several species of laboratory animals has been investigated. Determination of the phosphorus turnover in the genital organs of treated animals proved to be a significant guide to the action of pineal preparations. Doses of pineal extracts lower than those required for weight changes sufficed to produce changes in phosphorus metabolism.
Apparently contradictory results encountered originally were explained when findings were evaluated on the basis of the age of the test animal and the type of extract used. Thus, in immature and/or hypophysectomized animals, crude aqueous extracts stimulate the genital system, whereas in mature intact animals the same extract often has an inhibitory effect on the same organs. The inhibitory effect could be measured also in immature mice treated with gonadotrophic hormone and this proved useful in short-term experiments.
Crude glandular suspensions apparently contain both inhibitory and stimulatory principles. Partial separation of these was achieved through the use of trichloracetic acid, the supernatant fluid having predominantly inhibitory action while the stimulatory substance was found mainly in the precipitate.
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ABSTRACT
The mechanisms of lymphatic-vascular transfer across the ovarian vascular pedicle were studied in anaesthetized sheep 8–15 days after ovulation. [3H]Prostaglandin F2α (PGF2α), [14C]mannitol and [36Cl]Na were infused continuously into either a uterine lymphatic or a uterine vein and the kinetics of transfer into the adjacent utero-ovarian vein or ovarian plasma were studied. Transfer occurred according to the sequence [36Cl] > [14C] > [3H] indicating that PGF2α is not transferred by rapid diffusion, as with [36Cl]Na, nor by a paracellular route, as with [14C]mannitol, but by a slower process probably involving facilitated diffusion.
Transfer into the adjacent utero-ovarian vein or ovarian blood was greater when compounds were infused into a uterine lymphatic than into a uterine vein. Substantially more [3H]PGF2α occurred in the adjacent corpus luteum than either of the other compounds after a lymphatic infusion. Intra-lymphatic infusion of PGF2α stimulated the release of ovarian oxytocin but the effect was not confined to the adjacent ovary. Intravenous (jugular) infusion of PGF2α failed to stimulate ovarian oxytocin secretion whereas close-arterial infusion into the ovaries was effective, and the possibility was investigated that any systemic effect of PGF2α was mediated through neural mechanisms. Noradrenaline and acetylcholine were both effective in causing the release of ovarian oxytocin when infused close-arterially into the ovary. With infusions of acetylcholine, ovarian oxytocin secretion rate was increased over fivefold without any change in posterior pituitary release. Noradrenaline and acetylcholine produced a concomitant fall in ovarian blood flow, and neurotransmitter-induced ischaemia may have played a role in ovarian oxytocin release. The finding that PGF2α infused into a uterine lymphatic stimulates ovarian secretion of oxytocin, and that the effect is bilateral whereas PGF2α accumulation in ovarian tissue is unilateral, implies that its mechanism of action may not be solely directed at the luteal cell.
Journal of Endocrinology (1989) 122, 147–159