The mammalian caroti...

The carotid body (CB) in mammals is a small cluster of chemosensory and supporting cells located at the ca-rotid bifurcation. It has been proposed that the chemoreceptor glomus cells release a variety of neurotrans-mitters that trigger upon hypoxia an action potential through the afferent fibers, thus conveying the che-mosensory information to the central nervous system. By means of histochemical techniques the presence and distribution of certain metabolic enzymes was demonstrated in the CB of rats, guinea pigs and rabbits. In particular, we have revealed that the glomus cells expressed hydrolytic enzymes such as alkaline phos-phatase (AP), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and ATPase as well as oxidore-ductases including oxidases like monoamine oxidase (MAO) and dehydrogenases like succinate dehydroge