摘要:

The distribution of esterases within a cell can influence the rate and extent at which drugs containing ester linkages would be hydrolyzed. The objective of this study was to evaluate the subcellular distribution of esterases in the bovine eye. Ocular tissue homogenates were subjected to differential centrifugation to yield mitochondrial, microsomal and cytoplasmic fractions. Each fraction was then incubated with 1-or 2-naphthyl esters and its esterase activity determined. No esterase activity was detected in the mitochondrial fraction. For the corneal epithelium and iris-ciliary body about 80% of the esterase activity in the tissue homogenates, on a per milligram protein basis, was associated with the microsomes, the remainder was associated with the cytoplasm. Of the tissues studied, the irisciliary body had the highest esterase activity, 15 and 7 times that in the corneal epithelium and corneal stroma, respectively. The corneal endothelium was devoid of esterase activity. In comparison with the rabbit eye, the specific esterase activity in the bovine eye was lower. Surprisingly, unlike the rabbit, the corneal epithelium of the bovine eye was enzymatically less active than the stroma. Based on these preliminary data, it was concluded that the esterase activity varies with the tissue and that within a cell the esterases were distributed between the cytoplasm and the microsomes according to a ratio specific for a tissue.

ISSN:0271-3683    

DOI:10.3109/02713688209020024

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor

摘要:

In a group of chickens studied after lid suture in the first month post hatching an unusually high myopia was found (n=8 eyes; average: -21.87 Diopters). The non-operated eyes of these chicks had the same optical properties (n=4; +0.93 Diopters) as the eyes of the normal control chicks (n-12; +0.81 Diopters). Although enlargement of the whole eye occurred, the main determinant was an axial elogation (operated eyes, 18.0 mm; non-operated, 13.7 mm; normal controls, 14.7 mm). The axial change involves an enlargement of the posterior as well as the anterior segments of the eye. Despite several structural characteristics specific to chicks, their eyes can serve as a model for myopia research.

ISSN:0271-3683    

DOI:10.3109/02713688209020025

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor

摘要:

The concentration of copper ([Cu]) in the extracellular fluid compartments of rabbit eyes was found to increase approximately 30-fold during experimental uveitis, generally paralleling increases in [protein]. However, during the recovery phase the decrease in [Cu] lags behind the decrease in [protein]in some rabbits, suggesting the presence of abnormally high levels of non-protein-associated Cu. Intravitreal injection of CuSO4(6μg of Cu/eye) causes an inflammatory response and evidence of tissue damage. A better understanding of trace element metabolism is clearly required to further elucidate the mechanism of ocular inflammation and associated tissue damage.

ISSN:0271-3683    

DOI:10.3109/02713688209020026

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor

摘要:

Cutaneous basophil hypersensitivity (CBH) is an immunologic reaction extensively studied in the guinea pig. We elicited this reaction in the conjunctiva by systemically sensitizing guinea pigs to ovalbumin in incomplete Freund's adjuvant. Skin tests showed basophils in the skin one week after sensitization when challenged with ovalbumin. However, the conjunctiva showed an eosinophilic reaction with few basophils. This is compatible with other extracutaneous manifestation of the CBH reaction.

ISSN:0271-3683    

DOI:10.3109/02713688209020027

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor

ISSN:0271-3683    

DOI:10.3109/02713688209020028

出版商:Taylor&Francis    

年代:1982

数据来源: Taylor