Effects of Berberine on Intracellular Free Calcium in Smooth Muscle Cells of Guinea Pig Colon

Abstract

Aim: To investigate the effects and mechanism of berberine (Ber) on the intracellular free calcium concentration ([Ca²⁺]_i) in the smooth muscle cells of guinea pig colon. Methods: The changes of [Ca²⁺]_i were assayed by the biwavelength spectrophotometry with Fura 2-AM in the cell suspension of the smooth muscle cells, which were freshly isolated from guinea pig colon. Results: In the resting state, [Ca²⁺]_i in the HEPES-Ringer solution (CaCl₂ 1.5 mmol·l^–1) was (108 ± 9.4) nmol·l^–1 (n = 7). Ber had no significant effects on the resting [Ca²⁺]_i, but markedly inhibited the increase in [Ca²⁺]_iinduced by 60 mmol·l^–1 KCl in a concentration-dependent manner. The value of IC₅₀was 34.09 µmol·l^–1. 30 and 100 µmol·l^–1 Ber also inhibited the elevation of [Ca²⁺]_i evoked by 10 µmol·l^–1 Ach in a dose-dependent fashion in the presence or absence of extracellular Ca²⁺. In addition, Ber inhibited the elevation of [Ca²⁺]_i stimulated by cyclopiazonic acid (CPA) in a dose-dependent manner. This effect was more potent in the HEPES-Ringer solution (IC₅₀ = 37.79 µmol·l^–1) than Ca²⁺-free medium (IC₅₀ = 49.70 µmol·l^–1). Conclusions: Ber possessed an inhibitory effect on the influx of extracellular Ca²⁺ and Ca²⁺-release from intracellular stores in the smooth muscle cells of colon. That is to say Ber may be a blocker of Ca²⁺ channels.

Pingkui Enema Alleviates TNBS‐Induced Ulcerative Colitis by Regulation of Inflammatory Factors, Gut Bifidobacterium, and Intestinal Mucosal Barrier in Rats

“…The Pingkui enema used in the present study is modified from previous classic prescription “decoction of Radix Pulsatillae ” from “Treatise on Cold Pathogenic Diseases.” The main herb of “decoction of Radix Pulsatillae ” is Radix Pulsatillae , other three herbs are Phellodendri Chinensis Cortex, Rhizoma Coptidis , and Fraxini Cortex as complementary herbs, also has effects on decrease of hot detoxification according to theory of TCM pharmacology. Based on modern study, this four herbs also showed therapeutic properties on UC, Radix Pulsatillae has anti-inflammatory and immune-modulatory properties [ 32 ], Fraxini Cortex has obvious anti-inflammatory and analgesic effects [ 33 ], and berberine extracted from Rhizoma Coptidis and Phellodendri Chinensis Cortex can significantly inhibit the opening of delayed rectifier potassium channels and Ca 2+ activated potassium channels on the surface of guinea pig colonic smooth muscle cells, therefore, inhibit the contraction of colonic smooth muscle, and be used to treat abdomen diarrhea [ 34 ]. Besides the abovementioned four classical herbs, four other herbs were supplemented in Pingkui enema based on traditional TCM theory and recent observations.…”

Pharmacological and therapeutic effects of Berberis vulgaris and its active constituent, berberine

“…Berberine delays the small intestinal transit time (Yuan et al, 1994). Berberine also possesses an inhibitory effect on the influx of extracellular Ca 2+ and Ca 2+ -release from intracellular stores in the smooth muscle cells of the colon; that may affect the tonicity of the colon (Cao et al, 2001). Berberine exerts an anti-secretory action directly upon epithelial cells, probably by blocking K + channels (Taylor et al, 1999).…”

Effect of Ethanol Extracts of Three Chinese Medicinal Plants With Anti-diarrheal Properties on Ion Transport of the Rat Intestinal Epithelia

“…Huanglian also contains various alkaloids including berberine (1). The berberine alone may exert an anti-secreting action on intestinal epithelial cells by affecting K + channels (17) and may block Ca 2+ influx in the smooth muscle cells of guinea pig colon (18). This could moderately explain why the ethanol extract of Huanglian does not affect Na + or Cl -movement in this present study.…”