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Published on: April 24, 2016
Methotrexate-induced changes in rat parotid and submandibular gland function
Abstract:
Methotrexate (MTX) was injected intraperitoneally at a dose of 15 mg/kg into adult rats daily for three consecutive days. When compared with saline-injected, ad libitum-fed rats or pair-fed saline-injected rats, MTX decreased unstimulated parotid gland weight, RNA content, and amylase content. RNA content was also decreased in submandibular glands. The parotid and submandibular gland outputs of sodium and chloride, but not that of potassium, were decreased following MTX injection. Ductal perfusion demonstrated decreased net efflux of sodium and chloride from the excretory duct of the submandibular gland. The effects of MTX on unstimulated parotid gland weight, RNA content, and amylase content are consistent with its ability to inhibit protein synthesis through depletion of folate co-factors. However, the mechanism by which the alterations in ion transport occurred is not clear at this time.
Insights
Methotrexate (MTX) treatment in rats reduced salivary gland weight and function. This study investigated MTX
Area of Science:
- Biochemistry
- Physiology
- Pharmacology
Background:
- Methotrexate (MTX) is a chemotherapy agent and immunosuppressant.
- Salivary glands are crucial for oral health and digestion.
- Understanding MTX's effects on salivary glands is important for managing side effects.
Purpose of the Study:
- To investigate the effects of MTX on rat salivary gland function.
- To examine changes in gland weight, RNA, and amylase content.
- To assess the impact of MTX on ion transport in salivary ducts.
Main Methods:
- Adult rats received daily intraperitoneal injections of MTX (15 mg/kg) for three consecutive days.
- Salivary gland weight, RNA, and amylase content were measured.
- Sodium, chloride, and potassium outputs were analyzed in parotid and submandibular glands.
- Ductal perfusion was used to study ion transport in submandibular glands.
Main Results:
- MTX significantly decreased unstimulated parotid gland weight, RNA, and amylase content compared to controls.
- Submandibular gland RNA content was also reduced by MTX.
- Parotid and submandibular gland outputs of sodium and chloride decreased, while potassium output remained unchanged.
- Ductal perfusion revealed a reduced net efflux of sodium and chloride from the submandibular gland excretory duct.
Conclusions:
- MTX administration impairs salivary gland function, affecting weight, protein synthesis, and ion transport.
- The observed effects on gland weight, RNA, and amylase suggest inhibition of protein synthesis.
- The precise mechanism underlying MTX-induced alterations in salivary gland ion transport requires further investigation.
