Minamikawa J, Kikuchi H, Ishikawa M, Yamamura K, Kanashiro M
Department of Neurosurgery, Kyoto University, Osaka, Japan.
Acta Neurochir Suppl (Wien). 1994;60:104-6. doi: 10.1007/978-3-7091-9334-1_27.
Atrial natriuretic peptide (ANP) regulates fluid and electrolyte homeostasis in the central nervous system. In this study, we evaluated the effects of ANP on brain edema, intracranial pressure (ICP) and cerebral energy metabolism in congenital hydrocephalus in rats. Brain edema, indicated by the longitudinal relaxation time (T1), was evaluated by 1H-magnetic resonance imaging (MRI). The ICP was monitored with a miniature pressure-transducer with telemetric system. Cerebral energy metabolism, indicated by PCr/Pi ratio, was measured by 31P-magnetic resonance spectroscopy (MRS). The rats were given 10 microliters of ANP in the left cerebral ventricle. Three different concentrations of ANP were given; 0.2 (group I), 2.0 (group II) and 20.0 (group III) micrograms/10 microliters, respectively. 10 microliters of saline was injected into the ventricle of the control group rats. There were no significant changes of ICP, T1 value and PCr/Pi ratio among the control group, group I and group II. In group III, in contrast, ICP decreased significantly at 20 minutes after ANP administration and stayed at this ICP level for 60 minutes. The T1 value decreased and PCr/Pi ratio increased 30 minutes after ANP administration. This study revealed that intraventricularly administered ANP could decrease ICP, reduce brain edema and improve the cerebral energy metabolism in rats with congenital hydrocephalus.
心房利钠肽（ANP）调节中枢神经系统中的体液和电解质平衡。在本研究中，我们评估了ANP对大鼠先天性脑积水模型脑水肿、颅内压（ICP）和脑能量代谢的影响。通过1H-磁共振成像（MRI），以纵向弛豫时间（T1）为指标评估脑水肿情况。使用带有遥测系统的微型压力传感器监测ICP。以磷酸肌酸/无机磷（PCr/Pi）比值为指标，通过31P-磁共振波谱（MRS）测量脑能量代谢。向大鼠左脑室内注射10微升ANP。给予三种不同浓度的ANP，分别为0.2（I组）、2.0（II组）和20.0（III组）微克/10微升。向对照组大鼠脑室内注射10微升生理盐水。对照组、I组和II组之间的ICP、T1值和PCr/Pi比值无显著变化。相比之下，在III组中，ANP给药后20分钟ICP显著下降，并在该ICP水平维持60分钟。ANP给药后30分钟，T1值下降，PCr/Pi比值升高。本研究表明，脑室内注射ANP可降低大鼠先天性脑积水模型的ICP、减轻脑水肿并改善脑能量代谢。
