Differential regulation of alpha-calcitonin gene-related peptide and preprocholecystokinin messenger RNA expression in alpha-motoneurons: effects of testosterone and inactivity induced factors.
alpha-Calcitonin gene-related peptide expression in alpha-motoneurons is regulated by spinal cord transection, axotomy and testosterone, but to date there are no studies which examine the regulation of cholecystokinin expression in motoneurons. In the present study, we compared the regulation of preprocholecystokinin and alpha-calcitonin gene-related peptide messenger RNA levels in motoneurons of the spinal nucleus of the bulbocavernosus. Previously, we demonstrated that manipulations which decrease activity in target muscles of the spinal nucleus of the bulbocavernosus motoneurons increase alpha-calcitonin gene-related peptide message and peptide levels in spinal nucleus of the bulbocavernosus motoneurons. This muscle-nerve interaction is mediated by a soluble factor which is increased by castration. We now report that decreasing plasma testosterone levels decreased preprocholecystokinin messenger RNA levels. Testosterone replacement at the time of castration restored preprocholecystokinin messenger RNA levels to intact values. Injections of crude extracts prepared from denervated bulbocavernosus/levator ani into the homologous muscles of gonadally intact rats increased the levels of alpha-calcitonin gene-related peptide messenger RNA in spinal nucleus of the bulbocavernosus motoneurons. The levels of preprocholecystokinin messenger RNA did not differ in rats injected with denervated bulbocavernosus/levator ani extract or buffer, both of which were significantly higher than in intact, untreated rats. The results of the present experiments imply that levels of preprocholecystokinin and alpha-calcitonin gene-related peptide messenger ribonucleic acid are differentially regulated in spinal nucleus of the bulbocavernosus motoneurons.
Popper
P
P
Department of Anatomy and Cell Biology, UCLA School of Medicine 90024.
Abelson
L
L
Micevych
P E
PE
D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000096:biosynthesis* / Q000235:genetics; D002766:Cholecystokinin / Q000096:biosynthesis* / Q000235:genetics; D003714:Denervation; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology*; D005837:Genitalia, Male / Q000294:innervation; D017403:In Situ Hybridization; D008297:Male; D009046:Motor Neurons / Q000187:drug effects / Q000502:physiology*; D009919:Orchiectomy; D011498:Protein Precursors / Q000096:biosynthesis* / Q000235:genetics; D015347:RNA Probes; D012333:RNA, Messenger / Q000096:biosynthesis* / Q000235:genetics; D051381:Rats; D013116:Spinal Cord / Q000187:drug effects / Q000502:physiology*; D013739:Testosterone / Q000097:blood / Q000494:pharmacology*
D011498:Protein Precursors; D015347:RNA Probes; D012333:RNA, Messenger; D013739:Testosterone; C042082:preprocholecystokinin; D002766:Cholecystokinin; D015740:Calcitonin Gene-Related Peptide