Removal of the olfactory bulbs modifies the gonadal responses to photoperiod in the lesser mouse lemur (Microcebus murinus).

Biol Reprod

CNRS URA 1183, Laboratoire d'Ecologie Générale, MNHN, Brunoy, France.

Published: July 1993

AI Article Synopsis

  • The sexual activity of lesser mouse lemurs is influenced by photoperiod, with males experiencing testicular development and increased testosterone during long daylight periods (over 12 hours).
  • In contrast, under short daylengths, their testosterone levels and gonadal function regress significantly.
  • Olfactory bulb removal in males altered their reproductive responses to light; although they still reacted to photoperiod changes, there were delays and reduced testosterone levels, and they didn't show gonadal regression after long exposure to light.

Article Abstract

The sexual activity of the lesser mouse lemur, unlike that of most living primates, is clearly dependent on photoperiod. Males responded to long daylengths (> 12 h light/day) by rapid testicular development and an increase in testosterone levels reaching 65.8 +/- 1.5 ng/ml (n = 12) after 3 wk of inductive photoperiod. Levels were maintained unchanged until 14 wk of exposure to long photoperiod, when spontaneous gonadal regression was observed. Under short daylengths, intact males exhibited regressed gonadal function with low plasma concentrations of testosterone: 5.4 +/- 1 ng/ml. To investigate the effect of olfactory bulb deprivation on gonadal responses to photoperiod, 12 males were bulbectomized (BX) during exposure to either long (n = 8, BX1) or short (n = 4, BX2) daylengths. In both groups of BX males, responses to long or short daylengths were maintained. However, the timing and the amplitude of gonadal responses to photoperiod were modified; BX males underwent a significant delay in testis development and also had reduced testosterone levels (53.3 +/- 2.3 ng/ml and 37.3 +/- 0.9 ng/ml for BX1 and BX2 groups, respectively). Moreover, BX males did not exhibit spontaneous gonadal regression after 14 wk of exposure to long daylengths, indicating that the photorefractory state did not appear, at least under our experimental conditions. In this primate, olfactory bulbs exert an important effect on the neuroendocrinological control of reproductive responsiveness to photoperiod.

Download full-text PDF

Source
http://dx.doi.org/10.1095/biolreprod49.1.58DOI Listing

Publication Analysis

Top Keywords

+/- ng/ml
16
gonadal responses
12
responses photoperiod
12
exposure long
12
olfactory bulbs
8
lesser mouse
8
mouse lemur
8
photoperiod males
8
long daylengths
8
testosterone levels
8

Similar Publications

Vocal Fold Vibration Associated With Inspiratory Phonation-An Acoustic and Electroglottographic Study.

J Voice

December 2024

Department of Duquesne-China Health Institute, John G. Rangos Sr. School of Health Sciences, Duquesne University, Pittsburgh, PA; Speech Science Laboratory, Faculty of Education, The University of Hong Kong, Hong Kong SAR, China.

Article Synopsis
  • The study focused on inspiratory phonation (IP) and its differences from expiratory phonation (EP) in terms of voice quality and glottal vibratory characteristics.
  • Acoustic and electroglottographic analyses were conducted on the vowel /i/ produced by 43 vocally healthy adults to assess voice metrics like fundamental frequency and jitter.
  • Results showed distinct changes in glottal vibration during IP, highlighting its clinical significance and the need for more research to understand its role in diagnosing and treating voice disorders.
View Article and Find Full Text PDF

Introduction: Consistency of liquid food plays an important role in managing patients with dysphagia, which can be objectively evaluated by using IDDSI Flow Test and consistometry. The present study established the relationship between IDDSI Flow Test and consistometric measures, and examined the measurement limitations of each test associated with thickened liquids prepared using starch-based and xanthan gum-based thickening agents.

Methods: Thirteen thickened liquid samples of consistency ranging from IDDSI Level 1 (mildly thick) to Level 3 (moderately thick) were prepared using starch-based and xanthan gum-based thickeners.

View Article and Find Full Text PDF

Effect of Face Masks on Voice Quality Associated with Young and Older Chinese Adult Speakers.

J Voice

June 2024

Duquesne-China Health Institute, John G. Rangos, Sr. School of Health Sciences, Duquesne University, Pittsburgh, Pennsylvania. Electronic address:

Objectives: Face masks have become important after the pandemic, but the change in voice when wearing a face mask is still unclear. The study investigated the effect of face masks on the acoustic and perceptual characteristics of voice quality associated with young and older Chinese adults.

Methods: Voice samples of the sustained vowel /a/ and continuous speech produced by 44 older and 61 young adults with and without an ASTM level-3 surgical face mask were recorded and analyzed.

View Article and Find Full Text PDF

Stem cells are ubiquitously found in various tissues and organs in the body, and underpin the body's ability to repair itself following injury or disease initiation, though repair can sometimes be compromised. Understanding how stem cells are produced, and functional signaling systems between different niches is critical to understanding the potential use of stem cells in regenerative medicine. In this context, this review considers kynurenine pathway (KP) metabolism in multipotent adult progenitor cells, embryonic, haematopoietic, neural, cancer, cardiac and induced pluripotent stem cells, endothelial progenitor cells, and mesenchymal stromal cells.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!