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In vitro studies suggest that the G protein-coupled receptor (GPR) 30 is a functional estrogen receptor. However, the physiological role of GPR30 in vivo is unknown, and it remains to be determined whether GPR30 is an estrogen receptor also in vivo. To this end, we studied the effects of disrupting the GPR30 gene in female and male mice. Female GPR30((-/-)) mice had hyperglycemia and impaired glucose tolerance, reduced body growth, increased blood pressure, and reduced serum IGF-I levels. The reduced growth correlated with a proportional decrease in skeletal development. The elevated blood pressure was associated with an increased vascular resistance manifested as an increased media to lumen ratio of the resistance arteries. The hyperglycemia and impaired glucose tolerance in vivo were associated with decreased insulin expression and release in vivo and in vitro in isolated pancreatic islets. GPR30 is expressed in islets, and GPR30 deletion abolished estradiol-stimulated insulin release both in vivo in ovariectomized adult mice and in vitro in isolated islets. Our findings show that GPR30 is important for several metabolic functions in female mice, including estradiol-stimulated insulin release.

Reports of "Long-COVID", are rising but little is known about prevalence, risk factors, or whether it is possible to predict a protracted course early in the disease. We analysed data from 4182 incident cases of COVID-19 who logged their symptoms prospectively in the COVID Symptom Study app. 558 (13.3%) had symptoms lasting >28 days, 189 (4.5%) for >8 weeks and 95 (2.3%) for >12 weeks. Long-COVID was characterised by symptoms of fatigue, headache, dyspnoea and anosmia and was more likely with increasing age, BMI and female sex. Experiencing more than five symptoms during the first week of illness was associated with Long-COVID, OR=3.53 [2.76;4.50]. Our model to predict long-COVID at 7 days, which gained a ROC-AUC of 76%, was replicated in an independent sample of 2472 antibody positive individuals. This model could be used to identify individuals for clinical trials to reduce long-term symptoms and target education and rehabilitation services.

Abstract-The reactivity of the vascular wall to endothelin-1 (ET-1) is influenced by cholesterol, which is of possible importance for the progression of atherosclerosis. To elucidate signaling steps affected, the cholesterol acceptor methyl-␤-cyclodextrin (m␤cd, 10 mmol/L) was used to manipulate membrane cholesterol and disrupt caveolae in intact rat arteries. In endothelium-denuded caudal artery, contractile responsiveness to 10 nmol/L ET-1 (mediated by the ET A receptor) was reduced by m␤cd and increased by cholesterol. Neither ligand binding nor colocalization of ET A and caveolin-1 was affected by m␤cd. Ca 2ϩ inflow via store-operated channels after depletion of intracellular Ca 2ϩ stores was reduced in m␤cd-treated caudal arteries, as shown by Mn 2ϩ quench rate and intracellular [Ca 2ϩ ] response. Expression of TRPC1, 3, and 6 was detected by reverse transcriptase-polymerase chain reaction, and colocalization of TRPC1 with caveolin-1 was reduced by m␤cd, as seen by immunofluorescence. Part of the contractile response to ET-1 was inhibited by Ni 2ϩ (0.5 mmol/L) and by a TRPC1 blocking antibody. In the basilar artery, exhibiting less store-operated channel activity than the caudal artery, ET-1-induced contractions were insensitive to the TRPC1 blocking antibody and to m␤cd. Increased store-operated channel activity in basilar arteries after organ culture correlated with increased sensitivity of ET-1 contraction to m␤cd. These results suggest that cholesterol influences vascular reactivity to ET-1 by affecting the caveolar localization of TRPC1. Key Words: arterial smooth muscle Ⅲ methyl-␤-cyclodextrin Ⅲ caveolae Ⅲ endothelin Ⅲ store-operated Ca 2ϩ channels H ypercholesterolemia increases reactivity to endothelin-1 (ET-1) in experimental animals and humans. [1][2][3][4] This has been pointed out as one possible factor in the progression of atherosclerosis. [5][6][7] The mechanism of action has not been elucidated, although both endothelial dysfunction and altered smooth muscle reactivity have been proposed. 5 Lipoprotein particles may directly influence endothelial membrane-associated endothelial NO synthase activity by interfering with cholesterol-rich domains referred to as caveolae. 8 Although these effects modulate the endothelial influence on vascular tone, less is known regarding direct effects of cholesterol on vascular smooth muscle functions.Caveolae are 50-to 100-nm membrane invaginations that integrate many cellular receptor functions. 9 For instance, ET A receptors expressed in COS cells colocalize with the caveolae-associated protein caveolin. 10,11 The caveolar structure is disrupted after depletion of cholesterol with cyclodextrins, 12 and this correlates with a decreased contractility to ET-1, but not to depolarization or ␣ 1 -receptor stimulation, in endothelium-denuded rat caudal arteries. 13 Cholesterol might thus modulate the strength of caveolae-associated signaling, providing a basis for altered contractility in response to ET-1.Activation of the ET A receptor stimulates Ca 2ϩ inflow ov...