Microcirculation parameters in rats exposed to biotechnological preparations of Cordyceps militaris fungi

BACKGROUND: Our previous studies demonstrated that administration of extracts of Cordyceps militaris (L.) Fr. biomass and culture fluid resulted in significant changes in blood pressure and heart rate in rats. However, the effect of these fungal biotechnological products on microcirculation has not been studied. AIM: To determine changes in microcirculation parameters in rats exposed to C. militaris (L.) Fr. extracts. METHODS: The study used 30 male Wistar rats weighing 250–300 g, which were divided into three groups of 10 animals each. Group 1 served as a control; animals in group 2 received 0.5 mL of C. militaris culture fluid extract, and group 3 received 0.5 ml of C. militaris (L.) Fr. biomass extract. Microcirculation was studied using laser Doppler flowmetry with a Lazma-MC laser blood flow analyzer (second version). Both non-oscillatory and oscillatory parameters of tissue microhemodynamics were recorded. RESULTS: Intraperitoneal administration of an extract of the in vitro–obtained mycelial biomass of C. militaris (L.) Fr. (group 3) resulted in a 30.3% increase in tissue perfusion (p = 0.0026) due to increased endothelial metabolic activity, decreased sympathetic adrenergic pressor effects, and decreased precapillary sphincter and precapillary metarteriole tone resulting from Ca2+-dependent muscle relaxation. This was evidenced by significant increases in all oscillatory and non-oscillatory parameters of microcirculation. Following administration of C. militaris (L.) Fr. culture fluid extract (group 2), perfusion increased by 32.6% (p = 0.0016), endothelial rhythm by 55% (p = 0.0072), neurogenic rhythm by 77.9% (p = 0.0121), myogenic rhythm by 82.1% (p = 0.0099), and respiratory rhythm by 45.5% (p = 0.0370) compared to those in the control group, indicating the development of vasodilation. The vasotropic effects in groups 2 and 3 were comparable; however, the effects of C. militaris were somewhat more pronounced in group 2, which was attributed to the different concentrations of dry matter and biologically active substances in these biotechnological products. CONCLUSION: Thus, as the analysis of the study results showed, the administration of C. militaris to animals in groups 2 and 3 led to endothelium-dependent vasodilation, a decrease in peripheral resistance, an increase in blood flow into the nutritive microvascular bed, and improvement in venous outflow.