Distribution of the Cocaine and Amphetamine - Regulated Transcript (Cart) and Calcium Binding Proteins Immunoreactivity in the Preoptic Area of the Ram

Abstract

The aim of the study was to describe the distribution of cocaine and amphetamine-regulated transcript (CART) and calcium binding proteins (CaBPs) of EF-hand family, namely calbindin, calretinin, and parvalbumin in the preoptic area (POA) of the ram. Frozen sections were processed for a routine immunofluorescence labelling. CART, calbindin, and calretinin immunoreactivity was present in neurons and fibers of the preoptic area, whereas parvalbumin showed immunoreactivity only in the POA fibers. CART displayed from a moderate to low immunoreactivity in cells and a high immunoreactivity in fibers. The highest immunoreactivity of all studied CaBPs exhibited calbindin, whereas the lowest parvalbumin. The results of the present study suggest that among the studied CaBPs, calbindin is the most likely to be involved in the participation of the important regulatory functions in the ram’s POA and the rich CART innervation seems to be strictly related to its control of the reproduction.

Ontogeny of Neurons Containing Calcium‐Binding Proteins in the Preoptic Area of the Guinea Pig: Sexually Dimorphic Development of Calbindin

“…To the best of our knowledge, data on the distribution of CB, CR, and PV in the POA are very scarce and it is limited to some general observations of hypothalamus or overall mapping studies of the central nervous system of adult mammals (Celio, ; Fortin and Parent, ). More detailed description concerning expression of these proteins in the POA was reported only in the ram (Bogus‐Nowakowska et al ., ). In fact, studies concerning the distribution of CB are more abundant but these reports are usually restricted to a small part of the POA only, namely to the sexually dimorphic nucleus (Brager et al ., ; Sickel and McCarthy, ; Scallet et al ., ; Edelmann et al ., ; Bodo and Rissman, ; Orikasa and Sakuma, ; Gilmore et al ., ).…”

“…Interestingly, according to studies of Fortin and Parent () in the squirrel monkey the MPN is completely devoid of CB immunoreactivity. The pattern of CR immunoreactivity in the guinea pig is consistent with that reported in the squirrel monkey (Fortin and Parent, ) and ram (Bogus‐Nowakowska et al ., ) where CB immunoreactivity predominated over CR staining. PV immunoreactivity in the guinea pig (present study), ram, rat, and squirrel monkey was weak (Celio, ; Fortin and Parent, ; Bogus‐Nowakowska et al ., ).…”

“…It seems to be very interesting to check whether differences observed on the immunohistochemical level would be consistent with the mRNA level in the studied developmental stages. Generally, the distribution of CB in the guinea pig POA corresponds well with that described in adult rat (Celio, ) and ram (Bogus‐Nowakowska et al ., ), where many CB+ neurons were present in the medial preoptic region, especially in the MPN whereas in the LPA, only scattered cells occurred and in much lower concentration than in the adjoining nuclei. Interestingly, according to studies of Fortin and Parent () in the squirrel monkey the MPN is completely devoid of CB immunoreactivity.…”

“…POA neurons, besides GABA, estrogen and androgen receptors, express many neurotransmitters and neuropeptides (Bogus‐Nowakowska et al ., , ; Hermanowicz et al ., ; Bogus‐Nowakowska et al ., ) but there is a scarcity of data on coexpression profile of CaBPs‐containing neurons in this brain region. CaBPs are present in different neuronal populations, such as cholinergic, GABAergic, glutamatergic, and nitrinergic (Baimbridge et al ., ).…”

“…In the scientific literature, there is a general scarcity of data concerning distribution of CB, CR, and PV in the POA and the whole knowledge concerning this issue is limited only to some general studies of hypothalamus or overall mapping of the central nervous system of adult mammals (Celio, ; Sanghera et al ., ; Fortin and Parent, ). A detailed distribution of these proteins in the POA has been reported so far in the male sheep only (Bogus‐Nowakowska et al ., ). Actually, there are more reports referring to a presence of CB in the POA, however, these studies concentrated only on sexually dimorphic nucleus of the POA (Lephart et al ., ; Sickel and McCarthy, ; Brager et al ., ; Scallet et al ., ; Edelmann et al ., ; Bodo and Rissman, ; Orikasa and Sakuma, ; Gilmore et al ., ).…”