Using computerized analysis of hemodynamics in conscious unrestrained rats, we tested the effects of intracerebroventricular administration of ketanserin (50 ?g), a special 5-HT2 antagonist, on blood pressure (BP), blood pressure variability (BPV), baroreflex-blood pressure control (ABR-BP), and baroreflex-heart period control (ABR-HP). The result are as follows: (1) There was no significant depression of blood pressure after intracerebroventricular administration of ketanserin; (2) Ketanserin could significantly decreased BPV, and enhanced ABR-BP and ABR-HP; (3) The decreasing of BPV was associated with enhancement of ABR-BP, but these changes were no related to the level of BP, indicating that the hypotension induced by ketanserin was not related to the enhancement of ABR-BP; (4) There was no significant negative relationship between ABR-BP and BPV after intracerebroventricular administration of ketanserin.

A new method to measure arterial baroreflex-blood pressure control (ABR-BP) in conscious rats was established in our laboratory. ABR-BP was quantitatively determined by comparing the pressor responses to All before and after the blockade of the efferent pathway of baroreflex. It was found that there was a close relationship between Hood pressure variability and ABR-BP rather than arterial baroreflex-heart period control. ABR-BP was significantly lower in SHR and RVHR than in WKY rats. The lower ABR-BP in SHR was due mainly to the impairment of parasympathetic component

Objective To establish a prediction model for geriatric frailty syndrome(GFS)in elder-ly patients with acute ischemic stroke(AIS)after treatment.Methods Clinical data of 156 elderly AIS patients admitted to our hospital from January 2020 to December 2022 were collected and ret-rospectively analyzed.According to occurrence of GFS or not,they were divided into GFS group(n=57)and control group(n=99).The differences of clinical features were recorded and com-pared between the two groups of elderly AIS patients.Multivariate logistic regression model was used to analyze the risk factors for GFS in the elderly AIS patients.And a prediction model for GFS was constructed.Results Larger proportions of aged ≥80 years,diabetes,massive cerebral infarction and dysphagia were observed in the GFS group than the control group(P＜0.05,P＜0.01).Multivariate logistic regression analysis showed that aged ≥80 years(OR=2.890,95％CI:1.306-6.395,P=0.009),diabetes(OR=4.892,95％CI:2.172-11.018,P=0.000),massive cere-bral infarction(OR=3.363,95％CI:1.418-7.977,P=0.006)and dysphagia(OR=2.772,95％CI:1.123-6.844,P=0.027)were independent risk factors for GFS in the elderly AIS patients after treatment.A nomogram prediction model was constructed.Then the dataset was randomly divided into a training set and a validation set in a ratio of 7∶3.The AUC value was 0.840(95％CI:0.754-0.927)in the training set,and 0.676(95％CI:0.518-0.833)in the validation set.Hos-mer-Lemeshow Goodness-of-Fit test indicated that when the model was subjected to the valida-tion set,a Chi-square value of 14.394 and a P value of 0.072 were obtained.Conclusion Our no-mogram prediction model has good value in predicting the occurrence of GFS in elderly AIS pa-tients after treatment.