Effects of Pinealectomy and Exogenous Melatonin on the Thyroid Gland Activity Varies in Relation to Reproductive Status of Male Spotted Munia (Lonchura punctulata; Aves, Passeriformes)

2000 ◽  
Vol 31 (4) ◽  
pp. 437-449 ◽  
Author(s):  
S. K. Maitra ◽  
M. Dey ◽  
S. Chopra ◽  
R. Dey ◽  
A. Sengupta ◽  
...  
Keyword(s):  
Thyroid Gland ◽  
Reproductive Status ◽  
Exogenous Melatonin ◽  
Lonchura Punctulata ◽  
Thyroid Gland Activity

OVULATION AND THYROID FUNCTION IN THE RABBIT

1968 ◽  
Vol 41 (1) ◽  
pp. 85-89 ◽  
Author(s):  
K. BROWN-GRANT
Keyword(s):  
Thyroid Gland ◽  
Thyroid Function ◽  
Peripheral Blood ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Short Term ◽  
Disappearance Curve ◽  
Serial Measurements ◽  
Thyroid Gland Activity ◽  
Blood Radioactivity

SUMMARY Serial measurements of peripheral blood 131I content beginning 96–120 hr. after the injection of radioactive iodide in rabbits were made to study possible short-term changes in thyroid gland activity after mating. No changes in the disappearance curve of blood radioactivity were detected after matings that induced ovulation or after the injection of human chorionic gonadotrophin. A dose of 12·5 m-u. thyrotrophin intravenously produced gross changes in the blood 131I levels, and mating was shown not to modify the response to this dose of thyrotrophin. It is concluded that, when ovulation is induced by mating in this species, no change in thyrotrophin secretion occurs; this finding is in contrast to results in species that ovulate 'spontaneously'.

Seasonal Variation in Thyroid Gland Activity in Deermice.

1962 ◽  
Vol 110 (1) ◽  
pp. 128-131 ◽  
Author(s):  
B. E. Eleftheriou ◽  
M. X. Zarrow
Keyword(s):  
Seasonal Variation ◽  
Thyroid Gland ◽  
Thyroid Gland Activity

THE INDUCTION OF OVULATION DURING PREGNANCY IN THE RAT

1969 ◽  
Vol 43 (4) ◽  
pp. 529-538 ◽  
Author(s):  
K. BROWN-GRANT
Keyword(s):  
Thyroid Gland ◽  
Early Pregnancy ◽  
Concentration Ratio ◽  
Ovarian Follicles ◽  
Follicle Development ◽  
Induction Of Ovulation ◽  
Oestradiol Benzoate ◽  
The Relationship ◽  
Thyroid Gland Activity

SUMMARY Ovarian follicles develop to the stage where they are competent to ovulate in response to exogenous gonadotrophin at the same rate during early pregnancy as in a normal 4-day cycle in the rat. The length of time during which this competency is retained appears to be shorter than after the blockade of ovulation by pentobarbitone administered at pro-oestrus in rats that are not pregnant. Evidence from oviduct:plasma (O:P) and uterus:plasma (U:P) 131I ratio measurements indicating high progesterone and low oestrogen levels at this stage of pregnancy may be relevant to this finding. Some evidence for a 3-day cycle of follicle development after day 6 of pregnancy was obtained but the high O:P ratios suggest that little oestrogen secretion is associated with this. Oestradiol benzoate (6·25–100 μg.) administered after day 3 of pregnancy will induce ovulation when competent follicles are present. The thyroid:plasma (T:P) concentration ratio for 131I does not rise in association with ovulation induced by exogenous gonadotrophin. After oestrogen administration, the T:P ratio may increase regardless of whether ovulation is induced or not. The results are discussed in relation to the studies of other workers on the induction of ovulation during pregnancy and to earlier work on the relationship between ovulation and changes in thyroid gland activity.

Sign in / Sign up

Export Citation Format

Share Document