diff --git a/arbor/include/arbor/units.hpp b/arbor/include/arbor/units.hpp
index b7be90b7b..0146570d8 100644
--- a/arbor/include/arbor/units.hpp
+++ b/arbor/include/arbor/units.hpp
@@ -59,6 +59,7 @@ constexpr inline auto pA = pico  * A;
 
 constexpr inline auto V = ::units::precise::volt;
 constexpr inline auto mV = milli * V;
+constexpr inline auto uV = micro * V;
 
 constexpr inline auto  Hz = ::units::precise::second.pow(-1);
 constexpr inline auto kHz = kilo * Hz;
diff --git a/python/cells.cpp b/python/cells.cpp
index bd1eee744..5897ffd49 100644
--- a/python/cells.cpp
+++ b/python/cells.cpp
@@ -266,7 +266,9 @@ void register_cells(py::module& m) {
                std::optional<U::quantity> E_R,
                std::optional<U::quantity> V_m,
                std::optional<U::quantity> t_ref) {
-                auto cell = arb::lif_cell{std::move(source_label), std::move(target_label)};
+                auto cell = arb::lif_cell{};
+                cell.source = std::move(source_label);
+                cell.target = std::move(target_label);
                 if (tau_m) cell.tau_m = *tau_m;
                 if (V_th) cell.V_th = *V_th;
                 if (C_m) cell.C_m = *C_m;
diff --git a/test/unit/test_simulation.cpp b/test/unit/test_simulation.cpp
index 8fa4c08d5..17b61c901 100644
--- a/test/unit/test_simulation.cpp
+++ b/test/unit/test_simulation.cpp
@@ -124,11 +124,15 @@ struct lif_chain: public recipe {
     cell_kind get_cell_kind(cell_gid_type) const override { return cell_kind::lif; }
     util::unique_any get_cell_description(cell_gid_type) const override {
         // A hair-trigger LIF cell with tiny time constant and no refractory period.
-        lif_cell lif("src", "tgt");
-        lif.tau_m = 0.01*U::ms;           // time constant (ms)
-        lif.t_ref = 0*U::ms;              // refactory period (ms)
-        lif.V_th = lif.E_L + 0.001*U::mV; // threshold voltage 1 µV higher than resting
-        return lif;
+        auto E_L = 0_mV;
+        return lif_cell {
+            .source = "src",
+            .target = "tgt",
+            .tau_m  = 0.01*U::ms,      // time constant
+            .V_th   = E_L + 1.0*U::uV, // threshold voltage 1 µV higher than resting
+            .E_L    = E_L,
+            .t_ref  = 0*U::ms,         // refactory period (ms)
+        };
     }
 
     std::vector<cell_connection> connections_on(cell_gid_type target) const override {