Adult female albino rats were exposed to constant illumination of moderate intensity for 55–65 days; at the end of this period more than 95% had no macroscopically visible luteal tissue in their ovaries and more than 90% were sexually receptive. In these animals ovulation was consistently induced by mating. The major component of the mating pattern responsible for the induction of ovulation was penile intromission. Mounting without intromission was much less effective and the occurrence or non-occurrence of ejaculation did not affect the incidence of ovulation. Non-sexual 'stressful' stimuli or the injection of progesterone also induced ovulation in about 50% of animals. However, adrenal progesterone was not required for either the maintenance of sexual receptivity or mating-induced ovulation since adrenalectomized rats exposed to constant light also mated and ovulated.
The time-course of the secretion of luteinizing hormone (LH), determined by radioimmunoassay of plasma LH, also indicated that mating had effects on LH secretion independent of any action of progesterone. LH concentrations were high at 40 min and maximal at 60 min after mating but decreased thereafter while following the injection of progesterone the levels rose gradually and remained high until at least 360 min after the injection. Sodium pentobarbitone administration had little effect on LH secretion induced by mating but blocked ovulation in some animals. Mating-induced ovulation was not invariably associated with increased activity of the thyroid gland but an increase did occur when the mating stimulus was prolonged.
Journal of Endocrinology is committed to supporting researchers in demonstrating the impact of their articles published in the journal.
The two types of article metrics we measure are (i) more traditional full-text views and pdf downloads, and (ii) Altmetric data, which shows the wider impact of articles in a range of non-traditional sources, such as social media.
More information is on the Reasons to publish page.
| Sept 2018 onwards | Past Year | Past 30 Days | |
|---|---|---|---|
| Full Text Views | 18 | 1 | 0 |
| PDF Downloads | 21 | 1 | 0 |
Online ISSN: 1479-6805
Print ISSN: 0022-0795
Strengthening biomedical communities
to advance science and health
CONTACT US
Bioscientifica Ltd | Starling House | 1600 Bristol Parkway North | Bristol BS34 8YU | UK
Bioscientifica Ltd | Registered in England no 3190519
