Search Results
You are looking at 1 - 5 of 5 items for
- Author: H Hidaka x
- Refine by access: All content x
Search for other papers by M. Kato in
Google Scholar
PubMed
Search for other papers by M. Hagiwara in
Google Scholar
PubMed
Search for other papers by Y. Nimura in
Google Scholar
PubMed
Search for other papers by S. Shionoya in
Google Scholar
PubMed
Search for other papers by H. Hidaka in
Google Scholar
PubMed
ABSTRACT
Calmodulin has been identified in parathyroid cells and is thought to play an important role in the production or secretion of parathyroid hormone. However, a detailed investigation of calmodulinbinding proteins in parathyroid glands has not been conducted. In this study, we attempted to determine the presence of calmodulin-binding protein in human parathyroid adenoma by affinity chromatography. The eluted protein from a calmodulin-coupled Sepharose 4B column with EGTA was analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis which revealed a major protein band of M r 50 000. A Ca2+/calmodulin-dependent protein kinase activity was detected at the protein peak using dephosphorylated casein as a substrate. The 50 kDa band was identified as calcium/calmodulin-dependent protein kinase II (CaM-kinase II) by immunoblotting. The substrate specificity, pH dependency and affinity for calmodulin of this enzyme were identical to those of CaM-kinase II from rat brain. Also, the kinase activity was sensitive to KN-62, a specific inhibitor of CaM-kinase II. In total, 0·48 mg of this kinase was purified from 3 g human parathyroid adenoma.
Journal of Endocrinology (1991) 131, 155–162
Search for other papers by A. Nagasaka in
Google Scholar
PubMed
Search for other papers by H. Hidaka in
Google Scholar
PubMed
Search for other papers by H. Itoh in
Google Scholar
PubMed
Search for other papers by H. Nakagawa in
Google Scholar
PubMed
Search for other papers by K. Kataoka in
Google Scholar
PubMed
Search for other papers by A. Yamaguchi in
Google Scholar
PubMed
Search for other papers by K. Iwase in
Google Scholar
PubMed
Search for other papers by A. Nakai in
Google Scholar
PubMed
Search for other papers by T. Ohyama in
Google Scholar
PubMed
Search for other papers by T. Aono in
Google Scholar
PubMed
Search for other papers by S. Miyakawa in
Google Scholar
PubMed
Search for other papers by K. Kawase in
Google Scholar
PubMed
Search for other papers by K. Miura in
Google Scholar
PubMed
ABSTRACT
Adenylate cyclase and cyclic AMP phosphodiesterase activities in the thyroid gland were significantly reduced after hypophysectomy, followed by a gradual restoration of the enzyme activities to the levels seen in sham-operated rats whereas a slight and persistent reduction was evident in guanylate cyclase and cyclic GMP phosphodiesterase activities in the same tissue. These changes in enzyme activities were restored by TSH administration but not by ACTH. The recovery of activity produced by TSH administration was inhibited by cycloheximide. Hypophysectomy, or TSH and cycloheximide administration, did not produce any significant changes in the concentrations of calmodulin, suggesting that the alteration of these enzyme activities is not induced by a decrease in the concentration of calmodulin. Since forskolin activation of adenylate cyclase did not restore the reduced activity in the hypophysectomized rat thyroid to the level found in the sham-operated control rat thyroid, we conclude that there is a reduction of the amount of enzyme after hypophysectomy rather than a change of the active site on adenylate cyclase. The spontaneous restoration of adenylate cyclase and cyclic AMP phosphodiesterase activities after hypophysectomy implies that cyclic AMP-metabolizing enzymes are responsive to an autoregulatory mechanism in thyroid follicular cells.
J. Endocr. (1985) 105, 363–369
Search for other papers by A. Nakano in
Google Scholar
PubMed
Search for other papers by M. Terasawa in
Google Scholar
PubMed
Search for other papers by M. Watanabe in
Google Scholar
PubMed
Search for other papers by K. Okazaki in
Google Scholar
PubMed
Search for other papers by S. Inoue in
Google Scholar
PubMed
Search for other papers by M. Kato in
Google Scholar
PubMed
Search for other papers by Y. Nimura in
Google Scholar
PubMed
Search for other papers by N. Usuda in
Google Scholar
PubMed
Search for other papers by T. Morita in
Google Scholar
PubMed
Search for other papers by H. Hidaka in
Google Scholar
PubMed
ABSTRACT
Neurocalcin (molecular weight 23 000 and 24 000) is a Ca2+-binding protein with three putative Ca2+-binding domains and is present in large amounts in nervous tissues. Neurocalcin isoproteins separated by C18 reverse-phase column chromatography are insoluble in buffer solution and it is impossible to determine the dissociation constant of neurocalcin with Ca2+. To overcome this difficulty, recombinant neurocalcin was synthesized, based on one of the cDNAs of the neurocalcin isoproteins. Stoichiometric titration experiments, using recombinant neurocalcin, indicated that this protein bound 2 mol Ca2+/mol protein and that the apparent dissociation constant for Ca2+ was 2·2 μmol/l, suggesting that neurocalcin plays a physiological role in cellular function. Immunoblotting showed that neurocalcin is present in the bovine adrenal gland in addition to the nervous tissues. Neurocalcin, identified by immunoblotting, was purified from the bovine adrenal gland. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of neurocalcin from the bovine brain showed 23 kDa and 24 kDa double bands, while SDS-PAGE of neurocalcin from the adrenal gland showed a single band of apparently 24 kDa, suggesting that the expression of neurocalcin isoproteins differs from tissue to tissue. The content of neurocalcin in the adrenal gland was 10 μg protein/100 g wet tissue. Immunohistochemical analysis showed the occurrence of neurocalcin in zona glomerulosa and adrenal medulla but not in zona fasciculata or zona reticularis. The restricted localization of neurocalcin in the adrenal gland suggests that a similar Ca2+ signal pathway may be present in zona glomerulosa and the adrenal medulla.
Journal of Endocrinology (1993) 138, 283–290
Search for other papers by T Mano in
Google Scholar
PubMed
Search for other papers by K Iwase in
Google Scholar
PubMed
Search for other papers by Y Sawai in
Google Scholar
PubMed
Search for other papers by N Oda in
Google Scholar
PubMed
Search for other papers by Y Nishida in
Google Scholar
PubMed
Search for other papers by T Mokuno in
Google Scholar
PubMed
Search for other papers by Y Itoh in
Google Scholar
PubMed
Search for other papers by M Kotake in
Google Scholar
PubMed
Search for other papers by R Masunaga in
Google Scholar
PubMed
Search for other papers by A Nakai in
Google Scholar
PubMed
Search for other papers by T Tujimura in
Google Scholar
PubMed
Search for other papers by A Nagasaka in
Google Scholar
PubMed
Search for other papers by H Hidaka in
Google Scholar
PubMed
Abstract
To investigate the effect of thyroid hormone on cardiac muscle dysfunction in hyper- and hypothyroid states, we evaluated cyclic 3′, 5′-nucleotide metabolism by measuring cyclic 3′, 5′-nucleotide phosphodiesterase activity and calmodulin concentrations in the cardiac muscles of hyper- and hypothyroid rats.
Cyclic AMP (cAMP) concentration was significantly high in the cardiac muscle of hyperthyroid rats and low in that from hypothyroid rats compared with control rats. Cyclic AMP and cyclic GMP phosphodiesterase activities were significantly decreased in the soluble fraction of cardiac muscle from hyperthyroid rats and markedly increased in this fraction in hypothyroid rats compared with normal animals. Calmodulin concentration was high in hyperthyroid and low in hypothyroid rats.
It was concluded from these findings that low cAMP-phosphodiesterase activity might, in part, bring about the high concentration of cAMP. Calmodulin was sigificantly high in the cardiac muscle of hyperthyroid rats and the reverse was the case in hypothyroid rats compared with normal rats. The implication is that, in hyper- and hypothyroid states, these changes may play an important role in cardiac function via their effect on cyclic nucleotide and Ca2+ metabolism.
Journal of Endocrinology (1994) 143, 515–520
Search for other papers by T Mano in
Google Scholar
PubMed
Search for other papers by K Iwase in
Google Scholar
PubMed
Search for other papers by I Yoshimochi in
Google Scholar
PubMed
Search for other papers by Y Sawai in
Google Scholar
PubMed
Search for other papers by N Oda in
Google Scholar
PubMed
Search for other papers by Y Nishida in
Google Scholar
PubMed
Search for other papers by T Mokuno in
Google Scholar
PubMed
Search for other papers by M Kotake in
Google Scholar
PubMed
Search for other papers by A Nakai in
Google Scholar
PubMed
Search for other papers by N Hayakawa in
Google Scholar
PubMed
Search for other papers by R Kato in
Google Scholar
PubMed
Search for other papers by A Nagasaka in
Google Scholar
PubMed
Search for other papers by H Hidaka in
Google Scholar
PubMed
Abstract
Hyper- and hypothyroid states occasionally induce skeletal muscle dysfunction i.e. periodic paralysis and thyroid myopathy. The etiology of these diseases remains unclear, but several findings suggest that the catecholamine-β-receptor-cAMP system or other messenger systems are disturbed in these diseases. In this context, we evaluated changes in the cyclic 3′,5′-nucleotide metabolic enzyme, cyclic 3′,5′-nucleotide phosphodiesterase (PDE) and calmodulin concentrations in skeletal muscles of hyper- and hypothyroid rats.
Activities of cyclic AMP-PDE were low in skeletal muscle both from hyper- and hypothyroid rats, and calmodulin concentration was high in hyperthyroid and low in hypothyroid rats, as compared with normal rats. DE-52 column chromatographic analysis showed that the cGMP hydrolytic activity in peak I and the cAMP hydrolytic activity in peak II were decreased in hypothyroid rats, whereas cAMP hydrolytic activity in peak III was unchanged. The cAMP hydrolytic activity in peak III was decreased in hyperthyroid rats, but the activities in peaks I and II were unchanged. These findings indicate that cAMP and calmodulin may have some role in skeletal muscle function in the hyperthyroid state, and that cAMP and calmodulin-dependent metabolism may be suppressed in the hypothyroid state.
Journal of Endocrinology (1995) 146, 287–292
