ANNALS OF ANATOMY Calcitonin Gene-Related Peptide (CGRP) expression in the human neonatal paravertebral ganglia Vassily Roudenok* Department of Human Anatomy, Minsk State Medical Institute, Dzerzhynsky Avenue 83, 220116 Minsk, Belarus Summary. The distribution of calcitonin gene-related pep- tide-immunoreactivity (CGRP-IR) in human neonatal paravertebral ganglia was demonstrated by the method of indirect immunohistochemistry. A marked population (up to 21%) of CGRP-IR neurons and varicose nerve fibres was observed. The number of calcionin gene-related pep- tide-immunoreactive neurons varied from ganglion to ganglion in the sympathetic trunk. In addition to its co- transmitter functions, the existence of CGRP in neonatal ganglionic nerve cells was suggested by its inductive and trophic actions on the growth and differentiation of neu- rons. Key words: Sympathetic ganglia - Human - Neonate - CGRP Introduction The investigation of neuropeptide distribution in the pe- ripheral nervous system has attracted more and more at- tention lately (Inagaki and Kito 1986; Lindh et al. 1987; Baffi et al. 1992; Hgppola et al. 1993). In addition to the classical neurotransmitters noradrenaline and acetylcho- line, neuropeptides also participate in autonomic chemi- cal transmission and induce different physiological actions on the target organs (Lundberg 1996). Calcitonin gene-related peptide (CGRP) can be counted among such substances. It includes 37 amino acid residues and is found in the neurons of the sympathetic ganglia and nerve fibres of the rat (Landis and Fredieu 1986), cat * Scholarship holder of the Medical University of Liabeck, Ger- many, Department of Anatomy (Head: Prof. Dr. med. Dr. h.c. Wolfgang Kiihnel) (Kummer and Heym 1988; Lindh et al. 1989), guinea-pig (Kummer and Heym 1991); Heym et al. 1993), pig (H~ip- pola et al. 1993) and human (Schmitt et al. 1988; Baffi et al. 1992). In the sympathetic ganglionic neurons CGRP coexists with acetylcholine, somatostatin, substance P and vasoactive intestinal peptide (Gibbins et al. 1987; Landis and Fredieu 1986; Lee et al. 1985; Lindh et al. 1987) and causes different biological effects on target organs in- cluding long-lasting vasodilatation (Brain et al. 1985; Pie- trowski and Foreman 1986; Franco-Cereda and Lundberg 1988; Stjfirne et al. 1991), increased cardiac contractility (Saito et al. 1986; Franco-Cereda et al. 1987, 1988), re- laxation of smooth muscle (Hua and Lundberg 1986; Maggi et al. 1987) as well as trophic actions (Hfigerstrand et al. 1990). Besides CGRP is widely involved in sensor functions (Gibson et al. 1984, 1988) and immunological interactions and carbohydrate metabolism (Buckley et al. 1991; Leighton and Foot 1995). However, despite a great number of studies, investiga- tions of the aspects of the development of calcitonin gene-related peptide in autonomic ganglia are extremely fragmental, and data concerning the paravertebral ganglia of human neonates are missing. Therefore, human neonate paravertebral ganglia were subjected to immunohistochemical examination with re- spect to the expression of calcitonin gene-related peptide. Material and methods Twelve stellate, thoracic (III, IV) paravertebral ganglia of human neonates (n = 4) were used in this investigation. The postnatal age of neonatal specimens was up to 2 days, the gestational age from 38 to 41 weeks. Stellate and thoracic ganglia were fixed with Zamboni's fixa- tive solution for 1-5 days at 4 °C. The tissue samples were subse- quently rinsed in 0.1 M sodium phosphate buffer at pH7.4 Ann Anat (2000) 182:465-469 © Urban & FischerVerlag http:llwww.urbanfischer.deljournalslannanat 0940-9602/00/182/5-465 $15.00/0