RESUMO
Based on previous observations indicating a role for collagen peptides in eliciting a positive feedback for collagen biosynthesis, this study was initiated to elucidate the effect of non-crosslinked collagen on granulation tissue formation in dermal excision wounds. The wounds were treated with either non-crosslinked or crosslinked native collagen, or left untreated as controls. Granulation tissue was analyzed for collagen type I mRNA, for levels of interstitial collagen and for the number of blood vessels. The results indicated significant increases in procollagen type I mRNA, in interstitial collagen, in the number of blood vessels and in epithelial advance in the non-crosslinked collagen-treated wounds relative to the untreated controls. It is assumed that the presence of non-crosslinked collagen in a healing wound enhances both procollagen type I biosynthesis and the repair process of dermal wounds, due to the more readily released collagen peptides derived from this exogenous collagen dressing.
Assuntos
Colágeno/fisiologia , Derme/fisiologia , Tecido de Granulação/irrigação sanguínea , Tecido de Granulação/fisiologia , Animais , Colágeno/farmacologia , Reagentes de Ligações Cruzadas , Derme/irrigação sanguínea , Derme/metabolismo , Derme/cirurgia , Feminino , Tecido de Granulação/metabolismo , Cobaias , Hidroxiprolina/biossíntese , Pró-Colágeno/biossíntese , Pró-Colágeno/genética , Ferimentos e LesõesRESUMO
Aldosterone concentration was measured in plasma, erythrocytes and skeletal muscles in 34 patients with Icenko-Cushing's syndrome (ICS). It was established that aldosterone levels in the erythrocytes and whole blood of these patients were elevated, while aldosterone content in the plasma and muscular tissue of the patients was normal. Only in a small group of patients (N = 4) aldosterone levels positively correlated with arterial pressure (BP) and central hemodynamic parameters. Following 10 minutes of headdown tilt (-15 degrees), erythrocyte aldosterone level in the group of healthy controls (N = 12) was markedly elevated, but not in the group of patients with ICS. The results of the study suggest that erythrocytes can be viewed as a mobile aldosterone "depot" and may operate to mediate depressor effects of certain hormones on central hemodynamics.
