OBJECTIVE: To evaluate expression of the alpha6 chain of type IV collagen in the glomerular basement membranes (GBM) of healthy dogs. SAMPLE POPULATION: Kidney specimens from 12 healthy dogs. For comparison, kidney specimens from 8 human subjects between 25 and 83 years old also were evaluated. PROCEDURE: Sections were immunolabeled with a monospecific antibody that cross-reacts with human and canine alpha6(IV) chains and examined by means of fluorescence microscopy. RESULTS: Immunolabeling of the alpha6(IV) chain was not observed in GBM of 6 dogs < or = 30 months old but was observed in GBM of the remaining 6 dogs, all of which were > or = 45 months old. Expression of the alpha6(IV) chain was not observed in GBM of the human subjects, regardless of the age of the subject. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that the alpha6(IV) chain is expressed in GBM of healthy dogs, but the expression is age-dependent. Composition and structural organization of type IV collagen in the GBM of healthy adult dogs is different from that described for other species.
OBJECTIVE: To evaluate expression of the alpha6 chain of type IV collagen in the glomerular basement membranes (GBM) of healthy dogs. SAMPLE POPULATION: Kidney specimens from 12 healthy dogs. For comparison, kidney specimens from 8 human subjects between 25 and 83 years old also were evaluated. PROCEDURE: Sections were immunolabeled with a monospecific antibody that cross-reacts with human and canine alpha6(IV) chains and examined by means of fluorescence microscopy. RESULTS: Immunolabeling of the alpha6(IV) chain was not observed in GBM of 6 dogs < or = 30 months old but was observed in GBM of the remaining 6 dogs, all of which were > or = 45 months old. Expression of the alpha6(IV) chain was not observed in GBM of the human subjects, regardless of the age of the subject. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that the alpha6(IV) chain is expressed in GBM of healthy dogs, but the expression is age-dependent. Composition and structural organization of type IV collagen in the GBM of healthy adult dogs is different from that described for other species.