Table 3.

Reported half-lives of basement membrane components.

Animal	Age or BW	Tissue	Component(s) examined	Method	Externally added Probe	Probe delivery method	Half-life	Ref
Rat	>16 weeks	Kidney	Entire GBM	Pulse-chase	AgSO4 (*)	Mixed in drinking fluid	On the order of months or years	[1]
Rat	100-115g	Kidney	Entire GBM	Pulse-chase	3H glycine, 3H proline	i.p. injection	>70 days	[2]
Rat	100-115g	Kidney	Entire GBM	Pulse-chase	3H leucine, 3H lysine, 3H phenylalanine	i.p. injection	16-45 days	[2]
Rat	230-250g	Kidney	Collagen portion of the GBM	Pulse-chase	3H proline	i.p. injection	15-17 days	[161]
Rat	300g	Kidney	Entire GBM	Pulse-chase	3H glycine, 3H proline, 14C proline	i.p. injection	> 10 days	[80]
Rat	Not specified	Kidney	GAGs in the GBM	Pulse-chase	35S sulphate	i.p. injection	~7 days	[162]
Rat	Not specified	Kidney	Entire GBM	Pulse-chase	35S sulphate	i.p. injection	1 – several days	[163]
Human	0-85 years	Kidney	Entire GBM	Glycation (**)	NA	NA	4.5 days	[81]
Rat	180g	Kidney	HSPGs in the GBM	Pulse-chase	35S sulphate	i.p. injection	5-20 hours	[79]
Mouse	Adult, 22-26g	Gut	Laminin	Pulse-chase	Anti-laminin antibody	i.v. injection	On the order of weeks	[164]
Rat	160-200g	Cultured renal glomeruli	HSPGs	Pulse-chase	35S sulphate	Added to medium	11-47 hours	[165]
Rat	160g	Kidney	Perlecan in the GBM	Pulse-chase	35S sulphate	s.c. injection	3–4 hours	[166]
Mouse	6-8 weeks	Lung	α3 laminin	Inducible knockout	NA	NA	30-60 days (***)	[167]
Drosophila	Embryo	Whole body	Type IV collagen	Mathematical modelling	NA	NA	7 hours	[50]
Drosophila	Embryo	Whole body	Perlecan	Mathematical modelling	NA	NA	10 hours	[50]

The table lists the half-lives of basement membrane components reported in literature, the origin of the samples (organism and tissue), the age or body weight of source animals, and the method used to infer the half-lives. The probes used for pulse-chase experiments, and the method for probe delivery are also shown. (*) Silver administered from drinking fluid accumulates in the glomerular basement membrane (GBM). GBM turnover was estimated by measuring the decay of silver level in the GBM after pulse-labelling. (**) The half-life of GBM proteins was calculated from the degree of non-enzymatic glycation of proteins naturally occurring with time. Lower glycation suggests higher turnover. For detail, see ref [81]. (***) This value may not reflect normal turnover because the knockout affected tissue physiology. BW, body weight; GAG, glycosaminoglycan; GBM, glomerular basement membrane; HSPG, heparan sulphate proteoglycan; i.p., intraperitoneal; i.v., intravenous; s.c., subcutaneous.