Kulkarni Upendra, Mahalingam Ravichandran, Pather S Indiran, Li Xiaoling, Jasti Bhaskara
Department of Pharmaceutics and Medicinal Chemistry, Thomas J Long School of Pharmacy and Health Sciences, University of the Pacific, Stockton, California 95211, USA.
J Pharm Sci. 2009 Feb;98(2):471-83. doi: 10.1002/jps.21436.
Porcine buccal mucosa has been extensively used as an in vitro model to study the permeability of various diffusants and to assess their potential to be delivered through the buccal route. The relative contribution of each component of the buccal mucosa on drug permeability was assessed in this study. The permeability of model diffusants decreased significantly with an increase in the mucosal thickness. A bilayer membrane model was developed to delineate the relative contribution to the barrier function offered by the epithelium and the connective tissue region. The decrease in permeability with mucosal thickness was attributed to the increase in the thickness of connective tissue. However, the epithelium acted as a primary barrier to permeation of all diffusants studied at a mucosal thickness up to 500 microm. In addition, the epithelium exhibited higher resistance to the permeation of hydrophilic diffusants than to lipophilic diffusants. With an increase in buccal mucosal membrane thickness, the lag time for the diffusants increased. Based on the analysis of permeation data, the buccal membrane, as a composite of epithelium and connective tissue, is considered as a heterogeneous permeation barrier. A mucosal tissue thickness of about 500 microm is recommended for in vitro transbuccal permeation studies since the epithelium remained the major permeability barrier for all diffusants at this thickness.
猪颊黏膜已被广泛用作体外模型，以研究各种扩散剂的渗透性，并评估它们通过颊途径递送的潜力。本研究评估了颊黏膜各成分对药物渗透性的相对贡献。随着黏膜厚度的增加，模型扩散剂的渗透性显著降低。建立了双层膜模型，以描述上皮和结缔组织区域对屏障功能的相对贡献。渗透性随黏膜厚度的降低归因于结缔组织厚度的增加。然而，在黏膜厚度达500微米时，上皮对所有研究的扩散剂的渗透起到主要屏障作用。此外，上皮对亲水性扩散剂渗透的阻力高于对亲脂性扩散剂的阻力。随着颊黏膜膜厚度的增加，扩散剂的滞后时间增加。基于对渗透数据的分析，颊膜作为上皮和结缔组织的复合体，被视为一种异质渗透屏障。建议体外经颊渗透研究采用约500微米的黏膜组织厚度，因为在此厚度下上皮对所有扩散剂仍是主要的渗透屏障。
