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Background: Activation of endothelial small conductance calcium-activated K+ channels (KCa2.3) and intermediate conductance calcium-activated K+ channels (KCa3.1) leads to vascular relaxation. We found endothelial KCa2.3 down-regulation in the corpus cavernosum diminishes erectile function., Aim: We hypothesized that in type-2 diabetic mice, the function of KCa2.3 and KCa1.1 channels is impaired in erectile tissue., Methods: Erectile function was measured, and corpus cavernosum strips were mounted for functional studies and processed for qPCR and immunoblotting., Outcomes: Effects of type 2 diabetes on erectile function, expression and function of calcium-activated potassium channels., Results: In anesthetized diabetic db/db mice, erectile function was markedly decreased compared to non-diabetic heterozygous db/+ mice, and the impairment was even more pronounced compared to normal C57BL/6 mice. qPCR revealed KCa2.3 and KCa1.1α channel expressions were upregulated in corpus cavernosum from db/db mice. Immunoblotting showed down-regulation of KCa2.3 channels in the corpus cavernosum from db/db mice. Acetylcholine relaxations were impaired while relaxations induced by the nitric oxide, donor SNP were unaltered in corpus cavernosum from db/db compared to C57BL/6 and db/+ mice. Apamin, a blocker of KCa2 channels, inhibited acetylcholine relaxation in corpus cavernosum from all experimental groups. In the presence of apamin, acetylcholine relaxation was markedly decreased in corpus cavernosum from db/db vs C57BL/6 and db/+ mice. An opener of KCa2 and KCa3.1 channels, NS309, potentiated acetylcholine relaxations in corpus cavernosum from db/+ and db/db mice. Iberiotoxin, a blocker of KCa1.1 channels, inhibited acetylcholine relaxation in corpus cavernosum from db/+ mice, while there was no effect in tissue from db/db mice., Clinical Translation: Erectile function in diabetic db/db mice was severely affected compared to heterozygous and control mice, findings suggesting the non-diabetic db/+ and diabetic db/db mice for translational purpose can be used for drug testing on, respectively, moderate and severe erectile dysfunction. The altered expressions and impaired acetylcholine relaxation in the presence of apamin compared to C57BL/6 mice may suggest decreased KCa1.1 channel function may underpin impaired endothelium-dependent relaxation and erectile dysfunction in diabetic db/db mice., Strengths & Limitations: The present study provides a mouse model for type 2 diabetes to test moderate and severe erectile dysfunction drugs. Decreased KCa1.1 channel function contributes to erectile dysfunction, and it is a limitation that it is not supported by electrophysiological measurements., Conclusion: Our results suggest that the contribution of iberiotoxin-sensitive KCa1.1 channels to relaxation is reduced in the corpus cavernosum, while apamin-sensitive KCa2.3 channels appear upregulated. The impaired KCa1.1 channel function may contribute to the impaired erectile function in diabetic db/db mice., Competing Interests: Conflicts of interest: One of the authors is Chief Scientific Officer and owner of shares in a biotech company, outside the submitted work. The other authors declare no conflicts of interest., (© 2022, International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.)

Background: Activation of endothelial small conductance calcium-activated K + channels (KCa2.3) and intermediate conductance calcium-activated K + channels (KCa3.1) leads to vascular relaxation. We found endothelial KCa2.3 down-regulation in the corpus cavernosum diminishes erectile function., Aim: We hypothesized that in type-2 diabetic mice, the function of KCa2.3 and KCa1.1 channels is impaired in erectile tissue., Methods: Erectile function was measured, and corpus cavernosum strips were mounted for functional studies and processed for qPCR and immunoblotting., Outcomes: Effects of type 2 diabetes on erectile function, expression and function of calcium-activated potassium channels., Results: In anesthetized diabetic db/db mice, erectile function was markedly decreased compared to non-diabetic heterozygous db/+ mice, and the impairment was even more pronounced compared to normal C57BL/6 mice. qPCR revealed KCa2.3 and KCa1.1α channel expressions were upregulated in corpus cavernosum from db/db mice. Immunoblotting showed down-regulation of KCa2.3 channels in the corpus cavernosum from db/db mice. Acetylcholine relaxations were impaired while relaxations induced by the nitric oxide, donor SNP were unaltered in corpus cavernosum from db/db compared to C57BL/6 and db/+ mice. Apamin, a blocker of KCa2 channels, inhibited acetylcholine relaxation in corpus cavernosum from all experimental groups. In the presence of apamin, acetylcholine relaxation was markedly decreased in corpus cavernosum from db/db vs C57BL/6 and db/+ mice. An opener of KCa2 and KCa3.1 channels, NS309, potentiated acetylcholine relaxations in corpus cavernosum from db/+ and db/db mice. Iberiotoxin, a blocker of KCa1.1 channels, inhibited acetylcholine relaxation in corpus cavernosum from db/+ mice, while there was no effect in tissue from db/db mice., Clinical Translation: Erectile function in diabetic db/db mice was severely affected compared to heterozygous and control mice, findings suggesting the non-diabetic db/+ and diabetic db/db mice for translational purpose can be used for drug testing on, respectively, moderate and severe erectile dysfunction. The altered expressions and impaired acetylcholine relaxation in the presence of apamin compared to C57BL/6 mice may suggest decreased KCa1.1 channel function may underpin impaired endothelium-dependent relaxation and erectile dysfunction in diabetic db/db mice., Strengths & Limitations: The present study provides a mouse model for type 2 diabetes to test moderate and severe erectile dysfunction drugs. Decreased KCa1.1 channel function contributes to erectile dysfunction, and it is a limitation that it is not supported by electrophysiological measurements., Conclusion: Our results suggest that the contribution of iberiotoxin-sensitive KCa1.1 channels to relaxation is reduced in the corpus cavernosum, while apamin-sensitive KCa2.3 channels appear upregulated. The impaired KCa1.1 channel function may contribute to the impaired erectile function in diabetic db/db mice. Comerma-Steffensen S, Prat-Duran J, Mogensen S, et al. Erectile Dysfunction and Altered Contribution of KCa1.1 and KCa2.3 Channels in the Penile Tissue of Type-2 Diabetic db/db Mice. J Sex Med 2022;19:697-710., (Copyright © 2022 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.)

Background: Atopic dermatitis (AD) is a chronic inflammatory skin disease expressed early in life. Disease development is primarily determined by as yet unknown genetic factors, leading to the accumulation of activated T lymphocytes in the skin., Objectives: To investigate the nature of these T cells., Methods: T-cell lines could be established from AD skin biopsies, but not from normal skin or AD peripheral blood, when placed in RPMI 1640 medium with 10% human AB serum, antibiotics, and the T-lymphocyte growth factors interleukins 2 and 4. The cell lines were subjected to phenotypic analysis using a fluorescence-activated cell sorter and compared with lymphocytes from AD and normal control peripheral blood., Results: T-cell lines from 22 of 24 consecutive skin biopsies taken from 24 adult patients with AD were established. All cells were T lymphocytes expressing several activation markers. A significant proportion of the lymphocytes had stable expression of a CD4+ CD8+ phenotype (26% +/- 6%; mean +/- SEM). Such double-positive T lymphocytes are normally only seen in the thymus and not in the peripheral immune system. CD4+ CD8+ cells in peripheral blood of the patients (12.5% +/- 3.3%) were also detected., Conclusions: We suggest that a basic pathophysiological change in AD may be a faulty maturation of the T-lymphocyte system, leading to skin inflammation with CD4+ CD8+ T lymphocytes resembling immature T cells. This is likely to lead to skewing of many immune reactions in the patients.

Infection of human monocyte-derived macrophages with CMV decreased the respiratory burst when cells were stimulated with opsonized zymosan or Pneumocystis carinii (P. carinii). Such an effect, though smaller, was also seen with heat-inactivated CMV, but only when triggered by zymosan. The effect was most pronounced in cells obtained from CMV antibody-negative donors. Dexamethasone further reduced the respiratory burst, both in uninfected and CMV-infected cells. Interferon-gamma increased the response in uninfected cells and, to a lesser extend, in cells treated with heat-inactivated CMV, whereas no effect was seen with infective CMV. No overt productive infection or cytopathology could be detected, however, the monocytes incubated with infective but also heat-inactivated CMV formed clusters, a phenomenon that was equally pronounced in cultures from CMV antibody positive and negative-donors. These results might help explain the worse prognosis of P. carinii pneumonia in patients coinfected with CMV and receiving dexamethasone.

Twenty-four patients, including 12 with meningitis, were admitted with meningeal symptoms and fever. Their serum and spinal fluid tumor necrosis factor-alpha (TNF alpha) levels were determined by ELISA. TNF alpha immunoreactivity was found in spinal fluid of 10 meningitis patients and one nonmeningitis patient, whereas 7 sera, 5 from meningitis patients, contained TNF alpha. Levels were significantly higher in spinal fluids than in serum samples, and the TNF alpha bioactivity of spinal fluids and sera was considerably below predictions based on ELISA measurements. Gel filtration chromatography demonstrated the presence of both polymeric (greater than 200 kDa) and oligomeric (10-40 kDa) TNF alpha in spinal fluid. Significant bioactivity was obtained only from samples containing oligomeric cytokine. In agreement with previous in vitro findings, these results strongly indicate that bioactive TNF alpha oligomers form inactive polymers and monomers, which could contribute to the observed in vivo discrepancies between immunoreactive and bioactive protein. Finally, the data support the concept of local central nervous system production of TNF alpha in meningitis.

The never-treated control group in the Oslo Study hypertension trial of middle-aged men 40-49 years old at entry (n = 379) was studied with respect to five-year change in blood pressure and its correlates. The study began in 1972 and ended in 1979, and each patient was followed for five years. Both baseline and rate of change of correlates were analyzed as independent variables versus rate of change in blood pressure as the dependent variable. Rate of change in serum triglycerides were found to be the strongest correlate of rate of change in blood pressure in this population of healthy mild hypertensives. In addition, rate of change in serum cholesterol and body weight made significant contributions in some analyses, but to a lower degree than did rate of change in triglycerides. The model predicts a substantial decrease in blood pressure if lipids and body weight are reduced. Rate of change in sodium, uric acid, and chloride concentrations were also associated with blood pressure change, but total degree of explanation of all explaining variables only accounted for 11-15% of total variation in annual blood pressure change.