Pernow J, Ohlén A, Hökfelt T, Nilsson O, Lundberg J M
Department of Pharmacology, Karolinska Institute, Stockholm, Sweden.
Regul Pept. 1987 Dec;19(5-6):313-24. doi: 10.1016/0167-0115(87)90173-x.
The presence of neuropeptide Y (NPY)-like immunoreactivity (-LI) in sympathetic perivascular nerves and the functional effects of NPY and noradrenaline (NA) on vascular tone were studied in skeletal muscle of various species. A dense network of NPY-LI was found around arteries and arterioles but not venules in the gluteus maximus muscle of man, gracilis muscle of dog, tenuissimus muscle of rabbit and quadriceps muscle of cat, rat, guinea pig and pig. The distribution of NPY-immunoreactive (-IR) nerves was closely correlated to the presence of tyrosine hydroxylase (TH) and dopamine-beta-hydroxylase (DBH)-positive fibers, two markers for noradrenergic neurons. Double-staining experiments revealed that NPY- and TH-IR as well as NPY- and DBH-IR nerve fibers around arteries and arterioles were identical. The veins and venules, however, lacked or had a very sparse innervation of NPY-, TH- and DBH-positive fibers. The NPY- and TH-IR nerves in quadriceps muscle of the guinea pig were absent after treatment with 6-hydroxydopamine. Lumbosacral sympathetic ganglia from the same species contained many NPY-positive cells which were also TH- and DBH-IR. NPY-LI was also detected by radioimmunoassay in extracts of skeletal muscle from guinea pig, rabbit, dog, pig and man as well as of lumbosacral sympathetic ganglia. The content of NPY-LI in skeletal muscle was relatively low (0.1-0.4 pmol/g), whereas lumbosacral sympathetic ganglia had a much higher content (48-88 pmol/g). NPY (10(-7) M) contracted arterioles in the tenuissimus muscle of the rabbit to a similar extent (by 65%) as NA (10(-6) M), as studied by intravital microscopy in vivo. NPY had no effect on the corresponding venules while NA caused a slight contraction of these vessels. In vitro studies of small human skeletal muscle arteries and veins revealed that NPY was more potent than NA in contracting the arteries, and the highest concentration of NPY (5 x 10(-7) M) caused a contraction of a similar magnitude as NA 10(-5) M. NA contracted veins from human skeletal muscle, while NPY had only small effects. It is suggested that NPY, together with NA, could be of importance for sympathetic control of skeletal muscle blood flow.
我们研究了不同物种骨骼肌中交感神经血管周围神经肽Y（NPY）样免疫反应性（-LI）的存在情况，以及NPY和去甲肾上腺素（NA）对血管张力的功能影响。在人类的臀大肌、狗的股薄肌、兔子的股薄肌以及猫、大鼠、豚鼠和猪的股四头肌中，发现动脉和小动脉周围存在密集的NPY-LI网络，但静脉周围没有。NPY免疫反应性（-IR）神经的分布与酪氨酸羟化酶（TH）和多巴胺-β-羟化酶（DBH）阳性纤维（去甲肾上腺素能神经元的两种标志物）的存在密切相关。双重染色实验表明，动脉和小动脉周围的NPY-IR与TH-IR以及NPY-IR与DBH-IR神经纤维是相同的。然而，静脉和小静脉缺乏或仅有非常稀疏的NPY、TH和DBH阳性纤维支配。用6-羟基多巴胺处理后，豚鼠股四头肌中的NPY-IR和TH-IR神经消失。来自同一物种的腰骶交感神经节含有许多NPY阳性细胞，这些细胞也是TH-IR和DBH-IR。通过放射免疫测定法还在豚鼠、兔子、狗、猪和人类的骨骼肌提取物以及腰骶交感神经节中检测到了NPY-LI。骨骼肌中NPY-LI的含量相对较低（0.1 - 0.4 pmol/g），而腰骶交感神经节的含量要高得多（48 - 88 pmol/g）。通过体内活体显微镜观察研究发现，NPY（10⁻⁷ M）使兔子股薄肌中的小动脉收缩程度与NA（10⁻⁶ M）相似（达65%）。NPY对相应的小静脉没有影响，而NA使这些血管轻微收缩。对人类小骨骼肌动脉和静脉的体外研究表明，NPY在收缩动脉方面比NA更有效，NPY的最高浓度（5×10⁻⁷ M）引起的收缩幅度与NA 10⁻⁵ M相似。NA使人类骨骼肌静脉收缩，而NPY的作用很小。有人认为，NPY与NA一起可能对骨骼肌血流的交感神经控制具有重要意义。
