Pharmacological dissection of the cellular mechanisms associated to the spontaneous and the mechanically stimulated ATP release by mesentery endothelial cells: roles of thrombin and TRPV.

Endothelial cells participate in extracellular ATP release elicited by mechanosensors. To characterize the dynamic interactions between mechanical and chemical factors that modulate ATP secretion by the endothelium, we assessed and compared the mechanisms participating in the spontaneous (basal) and mechanically stimulated secretion using primary cultures of rat mesentery endothelial cells. ATP/metabolites were determined in the cell media prior to (basal) and after cell media displacement or a picospritzer buffer puff used as mechanical stimuli. Mechanical stimulation increased extracellular ATP that peaked within 1 min, and decayed to basal values in 10 min. Interruption of the vesicular transport route consistently blocked the spontaneous ATP secretion. Cells maintained in media lacking external Ca2+ elicited a spontaneous rise of extracellular ATP and adenosine, but failed to elicit a further extracellular ATP secretion following mechanical stimulation. 2-APB, a TRPV agonist, increased the spontaneous ATP secretion, but reduced the mechanical stimulation-induced nucleotide release. Pannexin1 or connexin blockers and gadolinium, a Piezo1 blocker, reduced the mechanically induced ATP release without altering spontaneous nucleotide levels. Moreover, thrombin or related agonists increased extracellular ATP secretion elicited by mechanical stimulation, without modifying spontaneous release. In sum, present results allow inferring that the spontaneous, extracellular nucleotide secretion is essentially mediated by ATP containing vesicles, while the mechanically induced secretion occurs essentially by connexin or pannexin1 hemichannel ATP transport, a finding fully supported by results from Panx1-/- rodents. Only the latter component is modulated by thrombin and related receptor agonists, highlighting a novel endothelium-smooth muscle signaling role of this anticoagulant.

Detection and genotyping of HPV in urine samples from Chilean women attending primary health care centers.

Cervical cancer is the second most common malignant neoplasm in women worldwide representing approximately 10% of all types of cancers. Triage of women through cervical cytology has been an important strategy for the surveillance and control of new cases of cervical cancer. However, in many regions around the world cervical cytology has a low coverage compared to developed countries. The molecular detection of HPV is the most effective method to increase the screening sensitivity of women at risk of developing cervical cancer. There are very few studies about the efficacy of urine testing for detection of HPV in women followed up in primary health care centers. Consequently, the efficacy of using urine HPV screening in these populations has not been addressed yet. Here, we compared the detection of HPV in simultaneous urine and cervical samples of women followed up in primary health care centers. Urine and cervical samples were analyzed in 543 women attending at primary health care centers. HPV was detected by real time PCR, and HPV typing performed by PCR-RLB. A general HPV concordance of 86.2% (κ = 0.72) was determined between urine and cervical samples. The concordance for HPV-16 and 18 was almost perfect (κ = 0.82) and strong (κ = 0.77), respectively. The sensitivity and specificity for all HPV genotypes in urine using cervical samples as reference were 82.1 and 93.7%, respectively. The results showed that urine is a good alternative as clinical sample for HPV screening in women attending primary health care centers. Therefore, urine should be used as an alternative sample for increasing triage coverage either in refractory women participating in Pap surveillance programs or when cervical samples are not available.