Westlund K N, DiPette D J, Carson J, Holland O B
Department of Anatomy and Neurosciences, Marine Biomedical Institute, University of Texas Medical Branch, Galveston 77550.
Neurosci Lett. 1991 Oct 14;131(2):183-6. doi: 10.1016/0304-3940(91)90609-w.
Calcitonin gene-related peptide (CGRP), produced by alternative processing of the primary transcript of the calcitonin gene, is a potent vasodilator. We have shown that dietary calcium deficiency accompanied by decreased serum ionized calcium significantly decreases the neuronal content of CGRP in laminae I and II of the dorsal horn of the spinal cord in the growing rat. The spontaneously hypertensive rat (SHR) is characterized by decreased serum ionized calcium levels and is thought to most closely resemble human essential hypertension. To determine if the neuronal content of CGRP is decreased in the SHR compared to the Wistar-Kyoto (WKY) parent strain, CGRP was localized immunocytochemically in the dorsal horn of the spinal cord. The density of immunocytochemical staining was quantitated by computer-assisted image processing of laminae I and II of the upper thoracic spinal cord of 12-14 week old male SHR (n = 4) and WKY (n = 4) normotensive, control rats. The SHR had significantly decreased neuronal CGRP content compared to the WKY rats (107 +/- 5 vs 121 +/- 6 arbitrary units, P less than 0.01). In contrast, the neuronal density of substance P (SP), which frequently co-exists with CGRP in this neuronal population, was not different between the two groups (SHR, 91 +/- 6 (n = 4) vs WKY, 88 +/- 3 arbitrary units (n = 4)).
降钙素基因相关肽（CGRP）由降钙素基因初级转录本的可变加工产生，是一种强效血管舒张剂。我们已经表明，饮食中钙缺乏伴血清离子钙降低会显著降低生长中大鼠脊髓背角I层和II层中CGRP的神经元含量。自发性高血压大鼠（SHR）的特征是血清离子钙水平降低，被认为与人类原发性高血压最为相似。为了确定与Wistar-Kyoto（WKY）亲本品系相比，SHR中CGRP的神经元含量是否降低，采用免疫细胞化学方法对脊髓背角中的CGRP进行定位。通过计算机辅助图像处理对12 - 14周龄雄性SHR（n = 4）和WKY（n = 4）正常血压对照大鼠上胸段脊髓I层和II层的免疫细胞化学染色密度进行定量。与WKY大鼠相比，SHR的神经元CGRP含量显著降低（107±5对121±6任意单位，P < 0.01）。相比之下，在该神经元群体中经常与CGRP共存的P物质（SP）的神经元密度在两组之间没有差异（SHR，91±6（n = 4）对WKY，88±3任意单位（n = 4））。
