Analysis of cannabinoid receptor binding and mRNA expression and endogenous cannabinoid contents in the developing rat brain during late gestation and early postnatal period.

摘要: Cannabinoid CB1 receptors emerge early in the rat brain during prenatal development, supporting their potential participation events related to neural development. In present investigation, we completed earlier studies, analyzing receptor binding and mRNA expression by using autoradiography situ hybridization, respectively, of fetuses at gestational day (GD) 21 newborns postnatal days (PND) 1 5, comparison with adult brain. These analyses were paralleled quantitation levels anandamide its precursor, N-arachidonoyl-phosphatidylethanolamine (NAPE), 2-arachidonoyl-glycerol (2-AG), carried out gas chromatography / mass spectrometry tri-methyl-sylyl-ether derivatives. As expected, was detected GD21 a variety structures. most them, such as hippocampus, cerebral cortex, cerebellum, basal ganglia, limbic nuclei, there no marked differences density animals compared (PND1 5), although it markedly increased these regions adulthood. However, exception cerebellum and, part, caudate-putamen, pattern observed for clearly different from that receptor, which currently exhibited highest PND1 lowest This also seen basolateral amygdaloid nucleus, ventromedial hypothalamic medial habenula, other caudate-putamen particularly, higher ages. previously reported, specific white matter areas, corpus callosum, anterior commissure, fornix, fimbria, stria medullaris, terminalis, fasciculus retroflexum. With commissure progressively decreased PND5 until disappearing values PND1, but completely disappeared brain, whereas lesser than not thus dismissing possible presence glial cells rather neuronal axons. brainstem, an area rich matter, mostly correlated binding, exhibiting progressive decrease up atypical areas where detected. are proliferative regions, subventricular zones neocortex, striatum, nucleus accumbens. location only persisted striatal zone, We found measurable endogenous cannabinoids developing High 2-AG, comparable those measured GD21, significantly lower NAPE this fetal age Levels period reaching maximum By contrast, 2-AG peaked approximately twofold summary, all data demonstrate cannabinoid system, constituted ligands signaling pathways, is suggests role system key processes Synapse 33:181–191, 1999. © 1999 Wiley-Liss, Inc.