Localization of calcitonin receptor mRNA in the mouse brain: coexistence with serotonin transporter mRNA

To elucidate the sites of and mechanisms of analgesic effect of centrally i njected calcitonin, we examined expression of calcitonin receptor mRNA in t he mouse brain by in situ hybridization techniques. Calcitonin receptor mRN A was expressed in various brain regions, including the preoptic area, dors omedial hypothalamic nucleus, lateral hypothalamic area, periaqueductal gra y, dorsal raphe nucleus, locus coeruleus, lateral parabrachial nucleus, gig antocellular reticular nucleus alpha part, lateral paragigantocellular nucl eus, raphe magnus nucleus and solitary tract nucleus, which are known to pl ay important roles in pain modulation. In addition, a double in situ hybrid ization technique demonstrated the intense expression of calcitonin recepto r mRNA on serotonergic neurons in some raphe nuclei and the lateral paragig antocellular nucleus, suggesting the involvement of central serotonergic pa thways in analgesic effect of calcitonin. (C) 2000 Elsevier Science B.V. Al l rights reserved.