Induction of c-Fos-like and FosB-like immunoreactivity reveals forebrain neuronal populations involved differentially in pup-mediated maternal behavior in juvenile and adult rats

Abstract

Juvenile rats can exhibit maternal behavior after being exposed continuously to rat pups, a process called sensitization. Maternal behavior in juveniles is robust and is similar to adult maternal behavior (Mayer and Rosenblatt [1979] Dev. Psychobiol. 12:407–424; Gray and Chesley [684] J. Comp. Psychol. 98:91–99). In this study, immunocytochemical detection of the protein products of two immediate‐early genes, c‐fos and fosB, was used as a tool to identify forebrain neuronal populations involved in the maternal behavior of 27‐day‐old juvenile rats compared with 60‐day‐old adults. To sensitize them, rats were exposed continuously to foster pups. Once they were maternal, they were isolated from pups overnight, reexposed to pups for 2 hours, and then killed. Nonmaternal control animals also were isolated overnight and were either reexposed to pups for 2 hours or kept isolated from pups before killing. The lateral habenula (LH) was the only area in which both maternal juveniles and maternal adults had more c‐Fos‐immunoreactive (‐Ir) neurons compared with controls. In maternal adults, the number of neurons that expressed c‐Fos and FosB immunoreactivity increased in the medial preoptic area (MPO) and the ventral bed nucleus of the stria terminalis (BSTv), whereas the dorsal bed nucleus of the stria terminalis (BSTd) and the medial and cortical nuclei of the amygdala (MEA and COA, respectively) had increases only in the number of neurons that expressed c‐Fos immunoreactivity. In contrast, juveniles, whether or not they were maternal, had the same number of c‐Fos‐IR and FosB‐Ir neurons in all these areas. The adult‐like increase in the number of c‐Fos‐Ir neurons found in maternal juveniles suggests that the juvenile LH participates in the neural circuit that supports maternal behavior in an adult‐like manner. The lack of c‐fos or fosB induction in the MPO, BSTv, BSTd, COA, or MEA of maternal juveniles compared with maternal adults may reflect the immaturity of these brain regions in juvenile rats. Exactly what this immaturity consists of and when the responses of these regions become adult‐like remain to be determined. J. Comp. Neurol. 416:45–78, 2000. © 2000 Wiley‐Liss, Inc.

Seeking for Senile-Related Gene Expression in Cerebral Tissue of Senescence-Accelerated Mouse

“…And 24 fragments are strain specific or differential expression. Most of those genes are associated with aging and senile phenotypic pathologies, which include heat shock protein 8 (Hspa8) (Nakanishi and Yasumoto, 1997), ubiquitin specific protease 14 (USP14) (Gray et al, 2003), protein L-isoaspartate (D-aspartate) O-methyltransferase (DeVry and Clarke, 1999), glial cell line derived neurotrophic factor family receptor alpha 1 (GDFR1) (Remy et al, 2001), RAB14 (Longo, 2003), FBJ osteosarcoma oncogene B (FOSB) (Kalinichev et al, 2000)., ubiquinol-cytochrome c reductase complex 7.2 kD, (Dillin et al, 2002), 60S ribosomal protein L21 (Zhang et al, 2002), phenylalkylamine Ca2+ antagonist (emopamil) binding protein (Roy et al, 1999), fucosyltransferase 9 (Ameno et al, 2001), ferritin heavy chain (Ammendola et al, 1992) Note. Clones1-4 are aging specific expression fragments.…”

How early maternal separation and juvenile experience with pups affect maternal behavior and emotionality in adult postpartum rats

“…Other areas, such as the lateral habenula, the medial preoptic area, and the ventral bed nucleus of the stria terminalis, differed in c-Fos expression between maternal and nonmaternal adult animals, but not in juvenile animals (Drmic, Oxley, & Fleming, 2001;Kalinichev, Rosenblatt, Nakabeppu, & Morrell, 2000). This seems to suggest that although the lateral habenula and the bed nucleus are involved in juvenile and adult maternal behavior, other areas may not be mature enough for involvement in maternal behavior during the juvenile period.…”

The vertebrate social behavior network: Evolutionary themes and variations

“…First, each of the nodes has been implicated in the control of multiple forms of social behavior. These include aggression, appetitive and consummatory sexual behavior, various forms of communication, social recognition, affiliation, bonding, parental behavior and responses to social stressors (Kirkpatrick et al, 1994;Kollack-Walker and Newman, 1995;Bamshad and Albers, 1996;Coolen et al, 1997;Kollack-Walker et al, 1997;Wang et al, 1997;Lonstein et al, 1998;Morgan et al, 1999;Delville et al, 2000;Kalinichev et al, 2000;Gammie and Nelson, 2001;Heeb and Yahr, 2001;Sheehan et al, 2001;Ferguson et al, 2002;Cushing et al, 2003;Lim and Young, 2004). The nodes are also bidirectionally connected (Risold and Swanson, 1997b;Coolen and Wood, 1998;Dong and Swanson, 2004), and each area contains sex steroid receptors that are essential for the sexual differentiation and temporal coordination of social behavior (Morrell and Pfaff, 1978;Commins and Yahr, 1985;Simerly et al, 1990;Wood and Newman, 1995).…”