Cerebellin in the rat adrenal gland: gene expression and effects of CER and [des-Ser1]CER on the secretion and growth of cultured adrenocortical cells.
Cerebellin (CER) is a regulatory peptide, originally isolated from rat cerebellum, which derives from the cleavage of precerebellin (Cbln), three types of which (Cbln1-3) have been identified in humans and rats. CER is also expressed in several extra-cerebellar tissues, including adrenal gland, and evidence has been provided that CER exerts a modulatory action on human and rat adrenal gland. Hence, we have investigated the expression of Cbln1-3 mRNAs and CER protein-immunoreactivity (IR) in the various zones of rat adrenal glands, and the effects of CER and its metabolite [des-Ser(1)]CER (des-CER) on the secretion and growth of cultured rat adrenocortical cells. Reverse transcription-polymerase chain reaction showed high and low expression of Cbln2 mRNA in zona glomerulosa (ZG) and zona fasciculata-reticularis, respectively. Cbln1 was not expressed, and Cbln3 mRNA was detected only in ZG. No Cbln expression was found in adrenal medulla. Immunocytochemistry demonstrated the presence of CER-IR exclusively in the adrenal cortex, the reaction being more intense in ZG. As expected, ACTH (10(-8) M) markedly enhanced corticosterone secretion and lowered proliferation rate of cultured adrenocortical cells. CER was ineffective, while des-CER exerted an ACTH-like effect, but only at the lowest concentration (10(-10) M). Taken together, these findings allow us to conclude that CER is expressed in rat adrenal cortex, and to suggest that CER conversion to des-CER by endopeptidases is needed for CER to exert its autocrine-paracrine regulatory functions.
Rucinski
Marcin
M
Department of Histology and Embryology, School of Medicine, PL-60781 Poznan, Poland.
Albertin
Giovanna
G
Spinazzi
Raffaella
R
Ziolkowska
Agnieszka
A
Nussdorfer
Gastone G
GG
Malendowicz
Ludwick K
LK
D000311:Adrenal Glands / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D005260:Female; D005786:Gene Expression Regulation; D008297:Male; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D009419:Nerve Tissue Proteins; C046788:cerebellin