Minimally modified low-density lipoprotein upregulates mouse mesenteric arterial 5-HT 1B receptor in vivo via activation of the JAK2/STAT3 pathway

To explore whether minimally modified low-density lipoprotein (mmLDL) upregulates mesenteric arterial 5-hydroxytryptamine 1B (5-HT ) receptor expression by activating the JAK2/STAT3 signaling pathway. Mice were randomly divided into the following groups: the normal saline (NS), LDL, mmLDL, mmLDL+galiellactone (GL, a JAK2/STAT3 pathway inhibitor), and mmLDL+DMSO groups. The dose-response curve of mesenteric arterial ring constriction after administration of 5-carboxamidotryptamine (5-CT), an agonist of 5-HT , was recorded with a microvascular tensiometer. JAK2, p-JAK2, STAT3, p-STAT3, and 5-HT receptor protein expression levels were determined by Western blotting. 5-HT receptor mRNA levels were measured by RT-PCR. 5-HT receptor protein expression was determined by immunofluorescence. Injection of mmLDL into the tail vein significantly increased the contractile dose-response curve after 5-CT stimulation, as the E was 82.15 ± 6.15% in the NS group and 171.88 ± 5.78% in the mmLDL group (P