PMID: 6411518Jul 1, 1983Paper

Relation between acute pituitary responsiveness to gonadotropin releasing hormone (GnRH) and the ovarian cycle in the bullfrog, Rana catesbeiana

General and Comparative Endocrinology
P LichtR Barnes

Abstract

Freshly captured female bullfrogs (Rana catesbeiana) were challenged with a standard dose (2 micrograms) of gonadotropin-releasing hormone (GnRH) shortly before and at the onset of the spawning season (in early April and mid-May) to examine the relationship between pituitary responsiveness and ovarian stage; males were also tested in April. As shown previously, increments in plasma gonadotropins induced by GnRH were consistently lower in females than in males. There was little difference in average responsiveness between the two collections of females and results for these were similar to those obtained at other times of the year. A wide range of ovarian stages was represented at both collection times as evidence by plasma steroid profiles, but there was no correlation between the GnRH-induced increments in plasma FSH and LH and plasma levels of androgens (testosterone and 5 alpha-dihydrotestosterone), estradiol-17 beta, or progesterone in the 71 females tested. Thus, there is no evidence of a feedback effect of ovarian steroids on the pituitary responsiveness to acute GnRH stimulation in the frog as has been demonstrated in mammals.

References

Mar 1, 1975·Archives of Neurology·A Faden
Feb 1, 1974·The Journal of Clinical Endocrinology and Metabolism·M FerinW F White
Dec 1, 1972·The Journal of Clinical Endocrinology and Metabolism·S S YenY Ehara

❮ Previous
Next ❯

Citations

Feb 28, 2013·Reproductive Biology and Endocrinology : RB&E·Vance L TrudeauLisa Taylor
Jan 1, 1992·General and Comparative Endocrinology·J Sotowska-Brochocka, P Licht
Apr 22, 2016·Journal of Experimental Zoology. Part A, Ecological Genetics and Physiology·Ana Josefina Arias TorresLiliana Isabel Zelarayán

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.