Sheng li xue bao : [Acta physiologica Sinica]
-
The present study investigated the effects of intrathecal (i.t.) application of bovine adrenal medulla 22 (BAM22), an endogenous opioid peptide potently activating opioid receptors and sensory neuron-specific receptor (SNSR), on a model of complete Freund's adjuvant (CFA)-induced inflammatory pain. Unilateral, but not bilateral, inflammatory pain was induced by intraplantar (i.pl.) injection of CFA in one side, as indicated by the shortened paw withdrawal latency and the increased edema of paw. Paw withdrawal latency test, paw edema determination and immunohistochemistry were used in CFA-induced inflammatory pain model after i.t. administration of BAM22 or saline. ⋯ Furthermore, i.t. treatment of 10 nmol BAM22 evidently decreased the expressions of CFA-evoked neuronal nitric oxide synthase (nNOS)-positive cells and calcitonin gene-related peptide (CGRP)-immunoreactivity positive nerve fibers by 25.6% (P<0.01) and 25.2% (P<0.001) compared with saline group, respectively, at L3-L5 segments of the spinal cord. Small and medium CGRP-positive cells were 57.4% and 35.2% in dorsal root ganglion (DRG) in 10 nmol BAM22 group, respectively, which were remarkably lower than those in saline group (P<0.001). The present study suggests that BAM22 relieves CFA-induced thermal hyperalgesia in the early phase and resumes antinociceptive effects through down-regulation of nNOS and CGRP expressions in DRG and spinal cord, which is possibly mediated via SNSR.
-
There is a close correlation between type 2 diabetes mellitus (T2DM) and Alzheimer's disease (AD) in the course of pathophysiological processes. The neuroprotective action of glucagon-like peptide 1 (GLP-1), a latest drug for clinical treatment of T2DM, is being more deeply investigated at present, and a novel therapeutic strategy for AD with GLP-1 has been proposed boldly. This review mainly discussed the correlation of pathogenesis between T2DM and AD, the synthesis and secretion of GLP-1, the distribution and physiological effects of GLP-1 receptor in the brain, and the progresses on the study of GLP-1 in the treatment of AD.
-
Trigeminal neuralgia is a paroxysmal disorder with severely disabling facial pain and thus continues to be a real therapeutic challenge. At present there are few effective drugs for treatment of this pain. The present study was aimed to explore the involvement of BK(Ca) channels and Kv channels in the mechanical allodynia in a rat model of trigeminal neuropathic pain. ⋯ These results suggest that BK(Ca) channel agonist NS1619 and Kv channel antagonist 4-AP can significantly affect the rats' facial mechanical pain threshold after ION-CCI. Activation of BK(Ca) channels may be related to the depression of the primary afferent neurons in trigeminal neuropathic pain pathways. Activation of Kv channels may exert a tonic inhibition on the trigeminal neuropathic pain.
-
The aim of the present study was to evaluate the relation between fat mass (FM), fat free mass (FFM) and ventilatory function in children and adolescents. 1 174 healthy children and adolescents (583 males and 591 females) aged 10-18 years were selected from Heilongjiang Province through random sampling by means of questionnaire and physical examination, and measured for height, weight, waist to hip ratio (WHR), FM, FFM and ventilatory function. The data were analyzed by means of independent-samples t test, Pearson correlation analysis and multi-factors regression analysis. Regardless of sex, an independent positive correlation was found (P<0.001) between age and FFM index (FFMI). ⋯ The effect of FFM in predicting ventilatory function is higher in males than that in females. FM correlates negatively with ventilatory function in males, but not in females. The rapid growth of height and FFM are possibly the main reasons for growth spurt of lung function.
-
Accumulating evidence indicates an important role of hippocampal dendrite atrophy in the development of depression, while neuropeptide Y (NPY) participates in hippocampal dendrite growth. The present study was aimed to investigate the relationship between NPY and nitric oxide synthase (NOS) in chronic unpredictable mild stress (CUMS)-induced depression. CUMS-induced depression model was established in Sprague-Dawley rats. ⋯ Intrahippocampal microinjections of L-NAME suppressed the depression-like behavioral changes induced by CUMS or intrahippocampal microinjection of GR231118. In conclusion, reduced expression of NPY and increased expression of NOS in hippocampus may make significant contributions to CUMS-induced depression. These results suggest that the antidepressant function of NPY associates with down-regulation of NOS expression in hippocampus, possibly mediated via NPY-Y1 receptor.