Different Patterns of Vasoactive Intestinal Polypeptide (VIP)-Immunoreactive and Acetylcholinesterase (AChE)-Positive Innervation in the Internal Carotid Artery and Cerebral Arterial Tree of the Quail

Abstract

ABSTRACT. The innervation pattern of vasoactive intestinal polypeptide-immunoreactive (VIP-IR) nerves in the quail internal carotid artery (ICA) and cerebral arterial tree was investigated and compared with that of acetylcholinesterase-positive (AChE-P) nerves. The supply of VIP-IR nerves to the two arterial systems was distinctly richer than that of AChE-P nerves. It was focused mainly on the walls from the distal ICA to the caudal half of the anterior ramus (AR) through the cerebral carotid artery (CCA). Indeed, double staining clearly showed that numerous VIP+/AChE-axons were distributed over these arterial regions where VIP+/AChE+ or AChE+/VIP-axons were sporadic or often lacking. The finding that nerve bundles accompanying the ICA within the carotid canal contained abundant VIP+/ AChE-nerve cells suggests that cerebrovascular VIP-IR nerves in the quail have their major source at these neurons and enter the cranial cavity through the CCA. Another significant finding was that a small number of nerve cells, which were mostly stained for AChE alone and occasionally for VIP alone or both, occurred in the major arteries located more rostral than the middle AR. Thus, the quail cerebral arterial tree, at least the rostral segment of the anterior circulation, is multiply innervated by these three distinct categories of the extracranial and intracranial VIP-IR and AChE-P neurons. The rich innervation of cerebral arterial tree by nerves immunoreactive for vasoactive intestinal polypeptide (VIP) has been well established for mammals [6,19,22]. The coexistence of VIP immunoreactivity and acetylcholinesterase (AChE) activity in the same cerebral perivascular axons has also been disclosed using double staining in the rat [12]. There is conclusive evidence that the principal site of origin for cerebrovascular VIP-immunoreactive (VIP-IR) and AChE-positive (AChE-P) innervation is the sphenopalatine ganglion (SPG) [10,14,21]. Pharmacological experiments have shown that VIP acts as a nonadrenergic and noncholinergic vasodilator that is accompanied by accumulation of cyclic adenosine monophosphate, and modulates the nitric oxide (NO)-induced vasodilatation as a facilitator [9].A series of our histochemical studies has shown clear species difference in the density and distribution of AChE-P nerves supplying the internal carotid artery (ICA) and cerebral arterial system of birds [4,5,16,17]. However, information on cerebrovascular VIP-IR innervation has not yet been reported for avian species. So, we undertook to investigate the overall distribution and origin of VIP-IR nerves in the ICA and major cerebral arteries of the quail, and to correlate them with those of AChE-P nerves, utilizing the combination of double staining and quantitative analysis. MATERIALS AND MTHODSTwelve male or female adult Japanese quails (Coturnix coturnix japonica) at 50 days after birth, weighing 100-120 g, were used in this study. The birds were perfused through the left ventricle with Ringer's solution under ethyl ether anesthesia, followed by 100 ml ...

Development of Vasoactive Intestinal Polypeptide-Immunoreactive Nerves in the Major Cerebral Arteries of the Quail Anterior Circulation

“…In rat, cerebral perivascular VIP-IR nerves reach a peak density at one month of age that is maintained until the fourth month [2,11]. The present study confirms and extends the previous observation that VIP-IR neuronal projection to the rAR from the CCA, which is an indication for mature pattern of the quail cerebrovascular VIP innervation [3], has been accomplished in most of the young birds aged P15. It has also shown that there is no appreciable statistical distinction in the nerve density of the corresponding major arteries of the anterior circulation among the four age groups from P15 to adulthood (P50).…”

“…Recently, we have reported the unique pattern of cerebrovascular VIP-IR innervation in the adult Japanese quail that is distinctly different from the general mammalian pattern [3]. In this avian species, cerebral perivascular VIP-IR nerves have their major source at the same category of neurons in the nerve bundles accompanying the internal carotid artery (ICA) within the carotic canal, and mainly enter the cranial cavity through the cerebral carotid artery (CCA), the intracranial part of the ICA.…”