RFamide peptides, the novel regulators of mammalian HPG axis: A review.

The RFamide-related peptides (RFRPs) are the group of neuropeptides synthesized predominantly from the hypothalamus that negatively affects the hypothalamo-hypophyseal-gonadal (hypothalamic-pituitary-gonadal [HPG]) axis. These peptides are first identified in quail brains and emerged as the mammalian orthologs of avian gonadotropin inhibitory hormones. The RFRP-3 neurons in the hypothalamus are present in several mammalian species. The action of RFRP-3 is mediated through a G-protein-coupled receptor called OT7T022. The predominant role of RFRP-3 is the inhibition of HPG axis with several other effects such as the regulation of metabolic activity, stress regulation, controlling of non-sexual motivated behavior, and sexual photoperiodicity in concert with other neuropeptides such as kisspeptin, neuropeptide-Y (NPY), pro-opiomelanocortin, orexin, and melanin. RFamide peptides synthesized in the granulosa cells, interstitial cells, and seminiferous tubule regulate steroidogenesis and gametogenesis in the gonads. The present review is intended to provide the recent findings that explore the role of RFRP-3 in regulating HPG axis and its potential applications in the synchronization of reproduction and its therapeutic interventions to prevent stress-induced amenorrhea.

A study on the electrocardiography in dogs: Reference values and their comparison among breeds, sex, and age groups.

AIM: The present investigation was intended to generate some basic data on electrocardiography (ECG) parameters in different breeds and their alterations in respect to sex and age. MATERIALS AND METHODS: The present investigation was carried out on 239 owned dogs of 11 different breeds presented to the Institute Veterinary Clinic during 2018-2019. The animals, irrespective of breed and sex were grouped on the basis of their age groups. Recordings of rdiartR, BPL, India) at 25 mm/s paper speed and 10 mm=1 mV calibration keeping the animals on the right lateECG were performed by a single-channel ECG machine (Caral recumbence without any anesthesia. Heart rate, along with the amplitude and duration of different waves and complexes was measured. RESULTS: Heart rate did not vary significantly among breeds, sex, and different age groups. The highest heart rate has been reported in Doberman and the lowest in Beagle. The heart rate was lowest at the age group of 6 months-2.5 years and highest around 10.5-12.5 years irrespective of breed and sex. The incidence of sinus arrhythmia was mostly seen in older dogs. All the waves and complexes did not vary significantly between breeds, age, and sex except P duration which was significantly (p<0.05) higher in Golden retriever and Doberman breeds. CONCLUSION: The present investigation generated some reference values of ECG in dogs which will help the clinicians to diagnose different cardiac abnormalities through ECG.