- Email: [email protected]
Feeding suppression induced after infusion of parathyroid hormone into the rat third cerebroventricle
$1 O0
L O C A L I Z A T I O N OF THE GAP J U N C T I O N mRNA IN THE N E O N A T A L RAT BRAIN BY IN SITU H Y B R I D I Z A T I O N HISTOCHEMISTRY. A K I R A MATSUMOTO(1), Y A S U M A S A ARAI(1), A K I H I S A URANO(2) and SUSUMU HYODO* (2). (i) Department of Anatomy, Juntendo U n i v e r s i t y School of Medicine, Hongo, TokTo 113 and (2) D e p a r t m e n t of Physiology, Ocean Research Institute, U n i v e r s i t y of Tokyo, Nakano, Tokyo 164, Japan. Gap junctions are considered to play an important role in cell-to-cell communication. Possible p a r t i c i p a t i o n of gap junctions is presumed in the neuronal o r g a n i z a t i o n of the developing brain. We studied the cellular d i s t r i b u t i o n of the m R N A for gap junction p r o t e i n in the brain of rats at postnatal day 2 by using in situ h y b r i d i z a t i o n histochemistry. A c o m p l e m e n t a r y DNA specific for the mRNA for rat liver gap junction protein (connexin 32, a gift from Dr. D. A. Goodenough) was applied to in situ h y b r i d i z a t i o n on cryostat and p a r a f f i n sections of the middle level of the brain. The density of a u t o r a d i o g r a p h i c grains for connexin 32 mRNA on cryostat sections of the brain was much h i g h e r than that on p a r a f f i n sections. The process of paraffin embedding may result in degradation of connexin 32 mRNA in tissues. The autoradiographic signals for connexin 32 mRNA were found to distribute in various regions of the brain such as frontal cortex, hippocampus, thalamus, striatum and hypothalamus. These signals were localized on neurons, glial cells and ependymal cells. These results indicate that gap junction m R N A may be expressed in neural substrates in the neonatal rat brain.
26. Neuroendocrinology THE AROMATASE NEURON SYSTEM IN TIIEMONKEY FOREBRAIN DEMONSTRATED BY ANTIBODY AGAINST PLACENTAL ANTIGEN X-P,. K_QH SIIINODAAND SHIRe HORI, I)epartmcntof !~atomy, Kinki University School of Medicin_e 377-2 0hno-Higashi, 0sakasayama, Osaka 589, Japan, Biochemical and physiological data have indicated the presence of aro~atase which converts androgen into estrogen in the brain. The enzyme appears to be involved in brain sexual differentiation, control of gonado-
tropin secretion and triggering of puberty and sexual behavior in ~a~mals. To c l a r i f y the localization of arcaatase, the regional d i s t r i b u t i o n of the enzyme was i~unohistochemically examined in the monkey forebrain with a polyclonal antibody against human placental antigen X-P, (PAX). antigen complex associated with aromatase a c t i v i t y in cytochrome P-450 of estrogen synthesizing tissues. Brains of ketamine(3Omg/kg)/pentoMrbital(9On~g/kg) anesthetized male Japanese monkeys (Maraca fuscata fnscata, 18-18kg) were perfused with phosphate buffered O. 02% picric acid-4% paraformldehyde. After one week-postfixation, free-floating frozen sections were stained using the PAP-DAB-Nickel method. Many PAX i~mmoreaetive c e l l s were found in the ventral pallidum extending from the area surrounding the islands of Calleja to the subleaticular substantia ianomiuata. Other imunoreactive c e l l s were detected in the second layer of the cerebral cortex, in a dist i n c t neuronal cluster in the ~--4iocortieal zone of the amygdala a t a n t e r i o r levels, and in the nucleus of the diagonal band. In addition, diffusely reactive structures resembling axons were observed in the medial preoptic area, the hypothalaaic periventricular zone, the supraoptic nucleus, the hypothalazic paraventricular nucleus and the arcuate nucleus. Our r e s u l t s suggest that the m j o r neuron group of the central aromat i z i n g system is localized in the ventral pallidum (not in the preoptic area as previously reported), and that fibers from these c e l l s nay project to the precptico-hypothalamic regions involved in the sexual d i f f e r e n t i a t i o n or in the neuroendocrinergie system including the hypothalamo-hypophyseal tract.
F E E D I N G S U P P R E S S I O N INDUCED A F T E R INFUSION .02 P A R A T H Y R O I D H O R M O N E I~TO THE RAT THIRD CE~BROVENTRICLE. ~AMORU KUROKA~A , HIRONOBU YOS~IMATSU , HIRONOBU MACHIDQRI ~-, T 0 $ H I I ~ SAKATA*, SYUJI AOU ~ AND ~ E T S U R O HORI ~. D e p a r t m e n t of Internal Medicine I , D e p a r t m e n t of P h y s i o l o K y , F a c u l t y of Medicine, Kyush1! University, F u k u o k a 812, Japan. Peripheral functions of PTH are well known, but its p h y s i o l o g i c a l functions in the brain are still unknown. Rat PTH 1-34 at doses of i0, i00, 1000 ng/rat was infused t h r o u g h a chronic catheter into the third c e r e b r o v e n t r i c l e of W K A rats. F e e d i n g e l i c i t a t i o n was not induced after infusion of any doses during the light period. Food c o n s u m p t i o n during 24 hr was s u p p r e s s e d d o s e - d e p e n d e n t l y after infusion of rat PTH (p
L O C A L I Z A T I O N OF THE GAP J U N C T I O N mRNA IN THE N E O N A T A L RAT BRAIN BY IN SITU H Y B R I D I Z A T I O N HISTOCHEMISTRY. A K I R A MATSUMOTO(1), Y A S U M A S A ARAI(1), A K I H I S A URANO(2) and SUSUMU HYODO* (2). (i) Department of Anatomy, Juntendo U n i v e r s i t y School of Medicine, Hongo, TokTo 113 and (2) D e p a r t m e n t of Physiology, Ocean Research Institute, U n i v e r s i t y of Tokyo, Nakano, Tokyo 164, Japan. Gap junctions are considered to play an important role in cell-to-cell communication. Possible p a r t i c i p a t i o n of gap junctions is presumed in the neuronal o r g a n i z a t i o n of the developing brain. We studied the cellular d i s t r i b u t i o n of the m R N A for gap junction p r o t e i n in the brain of rats at postnatal day 2 by using in situ h y b r i d i z a t i o n histochemistry. A c o m p l e m e n t a r y DNA specific for the mRNA for rat liver gap junction protein (connexin 32, a gift from Dr. D. A. Goodenough) was applied to in situ h y b r i d i z a t i o n on cryostat and p a r a f f i n sections of the middle level of the brain. The density of a u t o r a d i o g r a p h i c grains for connexin 32 mRNA on cryostat sections of the brain was much h i g h e r than that on p a r a f f i n sections. The process of paraffin embedding may result in degradation of connexin 32 mRNA in tissues. The autoradiographic signals for connexin 32 mRNA were found to distribute in various regions of the brain such as frontal cortex, hippocampus, thalamus, striatum and hypothalamus. These signals were localized on neurons, glial cells and ependymal cells. These results indicate that gap junction m R N A may be expressed in neural substrates in the neonatal rat brain.
26. Neuroendocrinology THE AROMATASE NEURON SYSTEM IN TIIEMONKEY FOREBRAIN DEMONSTRATED BY ANTIBODY AGAINST PLACENTAL ANTIGEN X-P,. K_QH SIIINODAAND SHIRe HORI, I)epartmcntof !~atomy, Kinki University School of Medicin_e 377-2 0hno-Higashi, 0sakasayama, Osaka 589, Japan, Biochemical and physiological data have indicated the presence of aro~atase which converts androgen into estrogen in the brain. The enzyme appears to be involved in brain sexual differentiation, control of gonado-
tropin secretion and triggering of puberty and sexual behavior in ~a~mals. To c l a r i f y the localization of arcaatase, the regional d i s t r i b u t i o n of the enzyme was i~unohistochemically examined in the monkey forebrain with a polyclonal antibody against human placental antigen X-P, (PAX). antigen complex associated with aromatase a c t i v i t y in cytochrome P-450 of estrogen synthesizing tissues. Brains of ketamine(3Omg/kg)/pentoMrbital(9On~g/kg) anesthetized male Japanese monkeys (Maraca fuscata fnscata, 18-18kg) were perfused with phosphate buffered O. 02% picric acid-4% paraformldehyde. After one week-postfixation, free-floating frozen sections were stained using the PAP-DAB-Nickel method. Many PAX i~mmoreaetive c e l l s were found in the ventral pallidum extending from the area surrounding the islands of Calleja to the subleaticular substantia ianomiuata. Other imunoreactive c e l l s were detected in the second layer of the cerebral cortex, in a dist i n c t neuronal cluster in the ~--4iocortieal zone of the amygdala a t a n t e r i o r levels, and in the nucleus of the diagonal band. In addition, diffusely reactive structures resembling axons were observed in the medial preoptic area, the hypothalaaic periventricular zone, the supraoptic nucleus, the hypothalazic paraventricular nucleus and the arcuate nucleus. Our r e s u l t s suggest that the m j o r neuron group of the central aromat i z i n g system is localized in the ventral pallidum (not in the preoptic area as previously reported), and that fibers from these c e l l s nay project to the precptico-hypothalamic regions involved in the sexual d i f f e r e n t i a t i o n or in the neuroendocrinergie system including the hypothalamo-hypophyseal tract.
F E E D I N G S U P P R E S S I O N INDUCED A F T E R INFUSION .02 P A R A T H Y R O I D H O R M O N E I~TO THE RAT THIRD CE~BROVENTRICLE. ~AMORU KUROKA~A , HIRONOBU YOS~IMATSU , HIRONOBU MACHIDQRI ~-, T 0 $ H I I ~ SAKATA*, SYUJI AOU ~ AND ~ E T S U R O HORI ~. D e p a r t m e n t of Internal Medicine I , D e p a r t m e n t of P h y s i o l o K y , F a c u l t y of Medicine, Kyush1! University, F u k u o k a 812, Japan. Peripheral functions of PTH are well known, but its p h y s i o l o g i c a l functions in the brain are still unknown. Rat PTH 1-34 at doses of i0, i00, 1000 ng/rat was infused t h r o u g h a chronic catheter into the third c e r e b r o v e n t r i c l e of W K A rats. F e e d i n g e l i c i t a t i o n was not induced after infusion of any doses during the light period. Food c o n s u m p t i o n during 24 hr was s u p p r e s s e d d o s e - d e p e n d e n t l y after infusion of rat PTH (p