Amnesic effects of the anticholinergic drugs, trihexyphenidyl and biperiden: differences in binding properties to the brain muscarinic receptor

A comparison of scopolamine and biperiden as a rodent model for cholinergic cognitive impairment

“…To the best of our knowledge, neither BIP, nor any other m1 antagonists have been tested in paradigms assessing food motivation and/or free feeding behavior. Although it is possible that a higher dose of BIP would have yielded a reduction in motivation, this dose is comparable to dose conditions used in other behavioral studies (Jones and Shannon 2000; Kimura et al 1999; Liu 1996; Myers et al 2002; Myhrer et al 2008; Roldán et al 1997; Sipos et al 1999; 2001). …”

“…For instance, after systemic injections deficits have been reported in passive avoidance tasks (Fornari et al 2000; Kimura et al 1999; Kramer-Soares et al 2006; Roldán et al 1997), contextual fear conditioning (Kramer-Soares et al 2006; but see Sheffler et al 2009), spatial alternation (Bymaster et al 1993), and object recognition (Myhrer et al 2004; 2008). Furthermore, m1 agonists have been shown to improve DNMTP performance in animals which were cognitively impaired after cholinergic lesioning (McDonald et al 1998), SCOP administration or aging (Bartholomeo et al 2000), which suggests that enhanced m1 signaling can be sufficient in order to reverse memory deficits.…”

“…Evidence for a role in mnemonic processes in both rodents and humans is strongest for the postsynaptic muscarinic m1 receptor (e.g., Conn et al 2009; Fornari et al 2000; Kimura et al 1999; Kramer-Soares et al 2006; Roldán et al 1997; Wezenberg et al 2005). This receptor is predominantly located in brain regions thought to be important for learning and memory such as cortex and hippocampus; presence of the m1 receptor in the periphery is relatively limited (Caulfield 1993; Volpicelli and Levey 2004).…”

Modelling Alzheimer-like cognitive deficits in rats using biperiden as putative cognition impairer

“…Our results contrast with findings of Klinkenberg and Blokland [7] who reported that 3 mg kg −1 BIP impaired short term memory in a delayed nonmatching to position (DNMTP) task. Kimura et al [19] also found, in a passive avoidance task, dose-dependent amnesic effects in memory acquisition and retrieval induced by BIP (dose range: 0.1-10 mg kg −1 ). BIP was also shown to induce dose-dependent impairments of inhibitory avoidance performance, comparable to those produced by scopolamine [20].…”

“…Another explanatory hypothesis would be that BIP induced attention deficits. However, studies have shown no effect of 10 mg kg −1 in rats tested in an attention task [19].…”