Estrous cycle stage influences on neuronal responsiveness to repeated anxiogenic stress in female rats

Renewal of appetitive behavior depends on the gonadal hormonal state of the female rat. In this experiment the effect of female rat estrous cycle stage on renewal of appetitive behaviors is replicated and extended upon to understand how endogenous hormonal states around the estrous cycle drive renewal at the neuronal population level. Estrous cycle stage (i.e., proestrus (P, high hormone) or metestrus/diestrus (M/D, low hormone)) was considered during two important learning and behavioral expression windows: at extinction training and during LTM/renewal testing. First, rats in P during context-dependent extinction training but in some other stage of the estrous cycle during long-term memory and renewal testing (Different) were shown to exhibit more renewal of conditioned foodcup (but not conditioned orienting) behavior compared to rats in other estrous cycle groups. Next, cellular compartment analysis of temporal activity using fluorescence in situ hybridization (catFISH) was used to examine immediate early gene activity of Arc mRNA in neuronal populations after distinct context-stimulus exposures (i.e., extinction and acquisition test contexts). Arc mRNA expression patterns were examined in the prefrontal cortex (PFC), amygdala, hippocampus (HPC), and paraventricular nucleus of the thalamus. P-different rats showed differential neuronal population activity in the infralimbic cortex of the PFC, the lateral amygdaloid nucleus, and both CA1 and CA3 regions of the dorsal HPC. In each region P-different rats exhibited more co-expression and less specificity of Arc mRNA compared to other hormonal groups, indicating that renewal of appetitive foodcup behavior induces Arc mRNA in overlapping neuronal populations in female rats.

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Influence of estrous cycle stage on acquisition and expression of fear conditioning in female rats

Physiology & Behavior ◽

10.1016/j.physbeh.2021.113372 ◽

2021 ◽

pp. 113372

Author(s):

Milene C. Carvalho ◽

Karina Genaro ◽

Christie Ramos Andrade Leite-Panissi ◽

Thelma A. Lovick

Keyword(s):

Fear Conditioning ◽

Estrous Cycle ◽

Female Rats ◽

Estrous Cycle Stage

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Shifts in preferred learning strategy across the estrous cycle in female rats

Hormones and Behavior ◽

10.1016/j.yhbeh.2004.01.005 ◽

2004 ◽

Vol 45 (5) ◽

pp. 330-338 ◽

Cited By ~ 146

Author(s):

Donna L Korol ◽

Emily L Malin ◽

Kristine A Borden ◽

Rachel A Busby ◽

Julia Couper-Leo

Keyword(s):

Estrous Cycle ◽

Learning Strategy ◽

Female Rats

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The anorectic effect of fenfluramine is influenced by sex and stage of the estrous cycle in rats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00779.2004 ◽

2005 ◽

Vol 288 (6) ◽

pp. R1486-R1491 ◽

Cited By ~ 24

Author(s):

Lisa A. Eckel ◽

Heidi M. Rivera ◽

Deann P. D. Atchley

Keyword(s):

Food Intake ◽

Estrous Cycle ◽

Female Rats ◽

Male Rats ◽

Gonadal Hormone ◽

Estrous Female ◽

Male And Female Rats ◽

Daily Food ◽

Hormone Status ◽

Anorectic Effect

The controls of food intake differ in male and female rats. Daily food intake is typically greater in male rats, relative to female rats, and a decrease in food intake, coincident with the estrous stage of the ovarian reproductive cycle, is well documented in female rats. This estrous-related decrease in food intake has been attributed to a transient increase in the female rat's sensitivity to satiety signals generated during feeding bouts. Here, we investigated whether sex or stage of the estrous cycle modulate the satiety signal generated by fenfluramine, a potent serotonin (5-HT) releasing agent. To examine this hypothesis, food intake was monitored in male, diestrous female, and estrous female rats after intraperitoneal injections of 0, 0.25, and 1.0 mg/kg d-fenfluramine. The lower dose of fenfluramine decreased food intake only in diestrous and estrous females, suggesting that the minimally effective anorectic dose of fenfluramine is lower in female rats, relative to male rats. Although the larger dose of fenfluramine decreased food intake in both sexes, the duration of anorexia was greater in diestrous and estrous female rats, relative to male rats. Moreover, the magnitude of the anorectic effect of the larger dose of fenfluramine was greatest in estrous rats, intermediate in diestrous rats, and least in male rats. Thus our findings indicate that the anorectic effect of fenfluramine is modulated by gonadal hormone status.

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063 — (ROD0183) Voltage oscillations induced by intrahippocampal pilocarpine in female rats during the estrous cycle

Epilepsy & Behavior ◽

10.1016/j.yebeh.2014.08.096 ◽

2014 ◽

Vol 38 ◽

pp. 208-209

Author(s):

M.C.A. Rodrigues ◽

A.R. Isaac ◽

B.L.S. Andrade-da-Costa

Keyword(s):

Estrous Cycle ◽

Female Rats

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Sex Hormones Regulate Rat Hepatic Monocarboxylate Transporter Expression and Membrane Trafficking

Journal of Pharmacy & Pharmaceutical Sciences ◽

10.18433/j3ch29 ◽

2017 ◽

Vol 20 (1) ◽

pp. 435 ◽

Cited By ~ 2

Author(s):

Jieyun Cao ◽

Michael Ng ◽

Melanie A Felmlee

Keyword(s):

Sex Differences ◽

Membrane Protein ◽

Protein Expression ◽

Estrous Cycle ◽

Sex Hormones ◽

Membrane Trafficking ◽

Drug Disposition ◽

Membrane Expression ◽

Membrane Protein Expression ◽

Estrous Cycle Stage

Purpose: Monocarboxylate transporters (MCTs) are involved in the transport of monocarboxylates such as ketone bodies, lactate, and pharmaceutical agents. CD147 functions as an ancillary protein for MCT1 and MCT4 for plasma membrane trafficking. Sex differences in MCT1 and MCT4 have been observed in muscle and reproductive tissues; however, there is a paucity of information on MCT sex differences in tissues involved in drug disposition. The objective of the present study was to quantify hepatic MCT1, MCT4 and CD147 mRNA, total cellular and membrane protein expression in males, over the estrous cycle in females and in ovariectomized (OVX) females. Method: Liver samples were collected from females at the four estrous cycle stages (proestrus, estrus, metestrus, diestrus), OVX females and male Sprague-Dawley rats (N = 3 – 5). Estrus cycle stage of females was determined by vaginal lavage. mRNA and protein (total and membrane) expression of MCT1, MCT4 and CD147 was evaluated by qPCR and western blot analysis. Results: MCT1 mRNA and membrane protein expression varied with estrous cycle stage, with OVX females having higher expression than males, indicating that female sex hormones may play a role in MCT1 regulation. MCT4 membrane expression varied with estrous cycle stage with expression significantly lower than males. MCT4 membrane expression in OVX females was also lower than males, suggesting that androgens play a role in membrane expression of MCT4. Males had higher membrane CD147 expression, whereas there was no difference in whole cell protein and mRNA levels suggesting that androgens are involved in regulating CD147 membrane localization. Conclusions: This study demonstrates hepatic expression and membrane localization of MCT1, MCT4 and CD147 are regulated by sex hormones. Sex differences in hepatic MCT expression may lead to altered drug disposition, so it is critical to elucidate the underlying mechanisms in the sex hormone-dependent regulation of MCT expression. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.

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